Nnrtli  (Earolina  BtnU 
Ilmupraitg 


HI 


<s 


This  book  was  presented  by 

MILTON  M.  LEONARD,  D.V.M. 

TO  THE 

VETERINARY  MEDICAL  LIBRARY 


Z]!!.^tB!l'Jmmmsmimmizs  | 


S02161372  M 


This  book  is  due  on  the  date  indicated 
below  and  is  subject  to  an  overdue 
fine  as  posted  at  the  circulation  desk. 


EXCEPTION:  Date  due  will  be 
earlier  if  this  item  is  RECALLED. 


200M/09-98-981815 


THE  FORMAL  FUNDUS  OF  THE  EYE. 


A  TEXT  BOOK 


OF 


VETERINARY  OPHTHALMOLO&Y 


GEO.  G.  VAN  MATER,  M.D.,  D.V.S. 

Professor  of  Ophthalmology  in    the    American    Veterinary  College} 
Oculist  and  Aurist  to  Si.  Martha'' s  Sanitarium  and  Dispen- 
sary ;  Consulting  Eye  and  Ear  Surgeon  to  the  Tioenty- 
sixth  Ward  Dispensary  ;  Eye  and  Ear  SurgeoUy 
Brooklyn  Eastern  District  Dispensary,  Etc. 


ifLUSTRATED   BY  ONE  CHROMO  LITHOGRAPH  PLATE  AND 
SEVENTY-ONE  ENGRAVINGS 


NEW  YORK 

WILLIAM  R.  JENKINS  CO. 

PUBLISHERS 

851-S53  Sixth  Avenue 


CoPTBiGHT,  1897,  by  William  R.  Jenkins 

All  riohlJ  resei'ved 


Pkixtzd  by  titb 

Press  of  "Wilj.iam  R.  Jexkins  Co. 

New  York 


THIS    BOOK 

IS 
AFFECTIONATELY  DEDICATED 

BY   THE  AUTHOR 
TO 

HIS  MOTHER 


PREFACE. 


My  excuse  for  perpetrating  this  work  consists 
in  shifting  the  blame  on  the  students  who  so 
often  have  asked  me  to  recommend  something 
that  could  he  studied  without  necessitating  the 
perusal  of  many  pages.  And  so  this  is  the  result. 
I  lay  claim  to  but  little  originality,  although 
what  I  have  told  is  the  result  of  conscientious 
study,  supplemented  by  practice,  both  private  and 
clinical,  and  careful  observation.  Let  me  hope, 
therefore,  that  my  motives  will  be  taken  into 
consideration  by  any  critic  who  may  deem  this 
publication  worthy  of  notice. 


A  TEXT  BOOK 


YETERINARY  OPHTHALMOLOGY 


INTRODUCTION. 

The  visual  apparatus  consists  of  the  eyeballs  and 
their  accessory  parts.  The  means  of  communication 
to  the  brain  are  the  optic  nerves.  Each  eyeball 
{Bidbus)  forms  a  hollow  spherical  box,  blackened  in- 
teriorly, with  a  system  of  convex  lenses,  in  front,  for 
forming  images  of  external  objects,  and  the  retina 
behind,  which  is  the  perceptive  membrane.    The  whole 


Fig.  1.— Formation  of  an  image  in  the  eye.     (Landois.) 

By  following  the  rays  from  the  object  A  B,  it  may  be  seen  that  they  are 
brought  to  a  focus  on  the  retina,  where  a  small  inverted  image  is 
formed. 

is  likened  to  a  camera  obscura.     A  camera  obscura  is  an 
optical  apparatus,  consisting  of  a  darkened  chamber,  at 


6 


VETERINARY   OPHTHALMOLOGY. 


the  top  of  which  is  placed  a  box  or  lantern  containing  a 
convex  lens  and  sloping  mirror,  or  a  prism  combining 
the  lens  and  mirror.  The  rays  of  light  from  surrounding 
objects  are  received  by  the  lens,  and  the  mirror  reflects 
images  of  the  scenery  downwards  on  a  table  placed 
underneath  (invented  by  Batista  Porta  in  the  end  of  the 
16th  century).  Now  the  light  passes  through  the 
cornea,  aqueous  humor,  lens  and  vitreous  humor,  and  is 
focussed  on  the  retina.  The  retina  appreciates  both 
intensity  and  color.    Images  which  are  formed  on  the 


Fig.  2.— Scheme  of  accommodation.    (Lnndois.) 

The  right  side  of  the  figure  represents  the  condition  of  the  lens  during  ac- 
commodation for  a  new  object,  and  the  left  side  when  the  eye  is  at  rest. 
The  letters  indicate  the  same  parts  on  both  sides  ;  those  on  the  right 
side  are  marked  with  a  stroke.  A,  left,  B,  right  half  of  the  lens :  C, 
cornea  ;  S,  sclerotic  ;  OS,  canal  of  Schlemm  ;  VK,  anterior  chamber  ;  J, 
iris  ;  P,  margin  of  the  pupil ;  V,  anterior  surface  ;  H,  posterior  surface 
of  the  lens ;  R,  margin  of  the  lens  ;  F,  margin  of  the  ciliary  processes ; 
A  B,  space  between  the  two  former  ;  the  line  Z  X  indicates  the  thick- 
ness of  the  lens  during  accommodation  for  a  near  object ;  Z  Y  tha 
thickness  of  the  lens  when  the  eye  is  passive. 

retina  are  inverted.     (Fig.  1.)    These  impressions  are 
conveyed  to  the  brain  by  the  optic  nerves,  and  thence 


VETERINARY   OPHTHALMOLOGY.  7 

we  have  resulting — vision.  Vision  in  all  animals  de- 
pends on  the  sensibility  of  the  retina  (optic  nerve 
filaments)  to  the  vibration  of  luminous  rays.  The 
amount  of  light  admitted  to  the  eye  is  regulated  by  a 
curtain,  the  iris,  the  movements  of  which  are  reflex. 
The  eye  adjusts  itself  (accommodation)  for  distances,  so 
that  the  retina  is  properly  focussed  for  distance  and 
for  objects  near  by.  (Fig.  2.)  At  the  base  of  the 
horse's  eye  is  found  a  collection  of  pigment  cells — bril- 
liant— called  the  tapetum,  and  in  a  darkened  stall  one 
may  get  the  reflex  from  the  eye,  bluish  in  coloi-,  more 
of  a  yellow  in  the  ox  and  reddish-yellow  in  the  cat. 

In  the  horse  the  eyes  are  placed  in  their  orbits  in- 
clined toward  the  sides.    Only  a  portion  of  a  view  is 


Fig.  8. 

perfectly  appreciated   at   one   time,  the   surrounding 
being  less  and  less  distinct,  but  from  the  perfect  action 


8  VETERINARY   OPHTHALMOLOGY. 

of  the  extrinsic  muscles  the  bulbi  are  rotated  so  exten- 
sively and  with  such  harmony  that  the  field  is  quite 
extensive.  Where  rays  of  light  proceed  from  a  lumi- 
nous body,  they  always  pass  in  straight  lines,  forming 
in  their  divergence  a  cone,  the  apex  of  which  is  the 
luminous  body,  and  the  base  any  plane  which  may  in- 
tercept them.  So  long,  then,  as  they  travel  in  a  medium 
of  uniform  density,  so  long  will  they  travel  in  straight 
lines.  Rays  passing  from  a  rarer  to  a  denser  medium 
are  bent  toward  the  perpendicular  at  the  point  of  inci- 
dence. (Fig.  .3.)  Should  they  fall  upon  ?^polislied  sur- 
face perpendicularly,  they  will  be  reflected  in  a  straight 

line.  If  obliquely, 
they  will  be  reflected, 
and  the  angle  of  re- 
flection is  equal  to  the 
angle  of  incidence. 
(Fig.  4.)  If  they  pass 
^'^■*'  from    a  denser   to  a 

rarer  medium,  they  will  be  bent  from  the  perpendi- 
cular (see  Fig.  3). 

If  a  luminous  ray  passes  through  a  piece  of  glass, 
the  ray  striking  obliquely,  it  will  be  bent  toward  the 
l^erpendicular,  but,  on  its  passing  from  the  glass  to  the 
air  (denser  to  rarer),  it  will  be  bent  cmay  from  the  per- 
pendicular. We  have  seen  rays  of  light  passing 
through  plane  surfaces.  Let  us  see  it  through  curved 
surfaces.  It  is  supposed  the  circumference  of  a  circle 
is  made  up  of  a  number  of  small,  straight  lines.    Take 


VETERINARY   OPHTHALMOLOGY.  ^ 

a  double  convex  lens.     (Fig.  5.)    Rays  of  light  passing 
through  this  are  bent  toward  the  perpendicular,  and 


Fig.  5. 

Diagram  illustrating  the  composition  of  a  convex  lens  of    a  numbex  of 
plane  surf  acea. 

therefore  these  rays  come  to  a  focus ;  and  where  the 
focus  is,  we  will  find  light  and  heat,  because  of  the  num- 


Fig.  6. 


ber  of  light  and  heat  rays  converged  at  one  spot.    Re- 
member that  a  ray  strikmg  a  plane  perpendicularly 


10  VETERINARY   OPHTHALMOLOGY. 

will  not  be  acted  upon,  but  will  pass  through  un- 
changed, and  this  is  the  chief  axis. 

The  distance  between  the  central  point  of  the  lens  and 
the  focus  is  the  focal  distance.  If  the  diiection  of  the 
rays  are  reversed  and  tliey  proceed  from  a  luminous 
point  at  the  focus,  the  rays  will  emerge  from  the  lens, 
parallel. 

When  the  distance  of  the  light  from  the  lens  is 
equal  to  the  focal  distance,  the  focus  will  lie  at  the 
same  distance  on  the  opposite  side  of  the  lens,  or  ticice 
the  focal  distance. 

If  the  luminous  point  approach  the  lens,  the  focal 
point  is  moved  farther  away.  If  the  rays  proceed 
from  a  chief  point  on  the  chief  axis  between  the  lens 
and  principal  focus,  they  will  diverge  on  the  opposite 
side  of  the  lens,  and  not  come  to  a  focus.     (Fig.  7.)     In 


I 


Fig.  7. 

ordinary  lenses,  the  refraction  is  not  equal  in  amount 
at  the  center  and  periphery. 

Rays  passing  through  the  optical  center  are  not  re- 
fracted, while  those  which  pass  near  the  center  are  less 


VETEEINAKY   OPHTHALMOLOGY.  11 

refracted  than  those  which  pass  near  the  circumference ; 
so,  you  see,  the  nearer  the  circumference,  the  more 
the  amount  of  refraction.  This  is  called  spherical  ab- 
erration, which  maybe  corrected  as  follows  : — Increase 
the  density  of  the  central  part  of  the  lens,  which  will 
cause  it  to  act  more  strongly  on  the  rays.  Now  see : 
this  is  just  what  the  lens  (crystalline)  does  in  the  eye, 
as  it  is  more  dense  in  its  center  than  periphery.    Or, 


Fig.  8. 
Tlierays  passing  through  the  edges  of  the  lens  have  a  shorter  focal  dis- 
tance than  those  passing  nearer  to  the  center. 

placing  a  diaphragm  between  the  object  of  which  the 
image  is  to  be  formed  and,  the  lens,  thus  cutting  oft' 
those  rays  which  pass  through  the  peripheral  portion 
of  the  lens,  the  image  therefore  being  formed  by  the 
rays  passing  through  the  center.  This  is  also  a  con- 
dition existing  in  the  eye,  for  have  we  not  the  iris,  and 
what  is  the  iris  but  a  diaphragm,  which  is  capable  of 
modification?    Xow,  light,  after  all,  is   a   composite 


12  VETEKINAKY   OPHTHALMOLOGY. 

affair,  being  composed  of  seven  colors, — violet,  indigo, 
blue,  green,  yellow,  orange  and  red.  One  may  demon- 
strate this  by  using  a  triangular  jiiece  of  glass — a 
prism — and  intercepting  a  beam  of  light,  which  will  be 
split  up  into  its  component  parts,  the  red  rays  being 


Fig.  9. 

Diagram  illustrating  the  decomposition,  in  passing  through  a  prism,  of 
white  light  into  the  seven  colors  of  the  spectrum  (Biclard) :  r,  red » 
o,  orange  ;  j,  yellow  ;  v.  green  ;  b,  blue  ;  i,  indigo  ;  vi,  violet. 

refracted  the  least  and  the  violet  the  most.  It  is  not 
the  province  of  a  small  compilation,  such  as  is  repre- 
sented by  this  little  work,  to  give  full  details  in  the 
physiology  of  sight.  That  must  be  culled  from  your 
various  text-books  on  physiology.  That  point  at  which 
the  image  is  focused  on  the  retina  is  called  the  "  field  of 
projection."     Here  the  visual  purple  becomes  bleached 


VETEEINARY   OPHTHALMOLOGY. 


13 


rig.  10. 

Anterior  portion  and  ciliary  region  of  the  eye.  C,  cornea  ;  c  S,  Schlemmls 
canal ;  O  s,  ora  serrata ;  1  p,  pectinated  ligament  :  e  F,  Fontana's  space ; 
T,  tendinous  ring ;  m,  meridional  fibers  ;  c.  circular  fibers  of  the  ciliary 
muscle  ;  Z,  zone  of  Ziun.  The  full  lines  indicate  the  crystalline  lens, 
iris,  and  ciliary  body  in  a  state  of  rest,  the  dotted  lines  show  the  same 
in  a  state  of  acci  mmoJation. 


14 


VETERINARY   OPHTHALMOLOGY. 


- — undergoes  change — and  its  action  and  function  is  now 
the  subject  of  much  question. 

The  question  of  inverted  images,  etc.,  will  be  more 
fully  dealt  with  in  the  lecture-room.  Accommodation  is 
that  faculty  of  the  eye  of  adapting  itself  to  distances  of 
varying  degree,  and  is  accomplished  by  the  action  of  the 
ciliary  muscle  upon  the  capsule  of  the  lens,  through  the 
zonule  of  Zinn.  When  accommo- 
dated for  near  objects,  the  pupil 
contracts;  when 'for  more  distant 
objects,  the  obverse  is  the  case. 
These  changes  (contraction  and 
dilation)  are  reflex,  and  are 
brought  about  by  the  action  of 
two  sets  of  fibers  (muscular) — the 
sphincter,  which  are  circular,  sup- 
plied by  the  .3d  pair  (motor-oculi) ; 
and  the  dilator  pupillce,  which  are 
the  radiating  fibers, supplied  almost 
entirely  by  the  trigeminus  and  the 
■"'"^  cervical  sympathetic,  Now,  sup- 
p,  pigment  Uii  Of,  the  re-  po^©  wc  divide  the  3d,  what  results  ? 
tina  connected  \vith  a  DHates  of  coursc ;  and  why  ?    The 

rod.    n,  Cone  seated  on  ■ 

the  membrana  liniitans  Sympathetic  gcts  in  its  work  and  is 

externa.  .„,, 

in  lull  possession  of  the  field  ;  the 
dilator  fibers  contract,  and  a  wide  open  pupil  is  the 
result.  On  the  other  hand,  cause  a  solution  of  con- 
tinuity in  the  sympathetic,  and  contraction  is  the  re- 


VETERINARY   OPHTHALMOLOGY.  15 

suit.  The  sphincter  fibers  contract  and  narrow  down 
the  pupil.  If  both  nerves  be  stimulated  simultane- 
ously, we  will  observe  that  the  sphincter  set  are  the 
more  powerful,  for  contraction  will  ensue.  In  the  pre- 
sence of  bright  light  we  have  contraction.  Stimulation 
in  the  floor  of  Aqueduct  of  Sylvius  causes  contrac- 
tion. Pupillary  caliber  is  modified  by  action  of 
certain  drugs,  of  which  more  hereafter.  The  retinal 
action  and  its  results  are  far  from  being  satisfactorily 
explained  to  the  ophthalmic  student,  as  yet.  We  know 
that  it  is  the  rod  and  cone  layer  only,  which  is  con- 
cerned in  the  formation  of  the  image.  The  most  acute 
vision  is  at  the  macula  lutea,  or  yellow  spot.  We 
will  speak  of  only  the  rod  and  cone  layer  in  this  part 
of  our  little  brochure,  and  under  the  retina  will  delve 
deeper  into  its  layers. 

The  external  layer,  consisting  of  rods  and  cones 
closely  packed  together,  *'.  e.,  small  transparent  rods, 
end  on,  close  together,  and  scattered  among  them  with- 
out regularity,  a  cone  here  and  there.  At  the  macula 
we  find  numerous  cones  and  an  absence  of  rods.  Also 
at  this  place,  find  ganglionic  and  yellow  pigment  cells. 
Now,  remember,  light  is  a  sensation  only. 

Remember,  also,  we  spoke  of  the  visual  purple.  As 
yet  we  know  not  of  its  i^recise  function,  but  that  it  is 
concerned  in  the  perception  and  recognition  of  light, 
there  is  no  reasonable  doubt. 

The  movements  of  the  bulbus  in  its  socket  are  of 


16  VETERINARY   OPHTHALMOLOGY. 

the  universal  order  known  as  ball-and-socket  joint. 
Luminous  impressions  upon  the  retina  continue  for  a 
short  time  after  cessation  of  light.  If  a  bright  point, 
like  a  smouldering  or  glowing  match  end,  be  waved 
around  in  a  circle,  the  eye  follows  it  throughout,  but  if 
tlie  rapidity  of  its  motion  be  increased  it  appears  drawn 
out  into  a  curved  line,  and  with  higher  motion,  veiy 
fast,  it  becomes  a  complete  ring  of  light.  Sparks  from 
a  knife-grinder's  wheel  become  a  stream  of  light.  A 
circular  saw  with  large  teeth  presents  a  smooth  edge 
when  revolving  rapidly,  and  the  spokes  of  a  rapidly- 
turning  wheel  assume  the  appearance  of  a  glimmer- 
ing disc. 

A  brilliant  light  leaves  a  longer  impression  than  a 
dim  one.  When  an  electric  spark  is  seen,  it  has 
already  come  to  an  end,  the  interval  elapsing  before  its 
perception  by  the  observer  being  greater  than  its 
actual  duration.  The  momentary  closing  of  the  eye- 
lids in  winking  is  unnoticed,  and  why  ?  Because  the 
visual  impression  of  external  objects  continues  unim- 
paired during  the  interval  occupied  by  the  movements 
of  the  lids.  The  eyes  of  the  horse,  remember,  are  set 
obliquely.  Only  in  man,  apes  and  some  night-birds 
are  the  eyes  so  set  as  to  permit  visual  lines  directly 
ahead  in  parallels. 

The  bulbus  has  its  poles.  An  imaginary  line  from 
pole  to  pole  is  its  axis.  The  equator  is  at  right  angles 
to  the  axis,  so  we  may  have  meridians.    The  visual 


VETERINARY   OPHTHALMOLOGY.  17 

axis  corresponds  to  the  macula  lutea,  while  the  optic 
axis  extends  from  pole  to  pole. 

"We  are  not  aware  of  an  image  being  on  the  retina, 
nor  of  its  position  there,  but  only  of  the  stimulus  pro- 
duced, on  the  perceptive  nerve  elements  of  the  retina. 
So,  understand,  we  do  not  see  the  image,  but  the  object 
from  which  the  rays  emanate,  and  we  refer  the  sensa- 
tions in  their  direction.  For  instance,  if  an  image  is 
formed  on  the  upper  and  outer  quadrant  of  the  retina, 
we  refer  it  doxcmrard  and  imcard.,  from  which  direction 
the  rays  must  have  come.  At  this  point  a  word  on 
inverted  images: — The  great  advantage  of  inverted 
images  is,  that  for  a  given-size  pupil  a  much  larger 
picture  can  be  formed  on  the  retina  than  would  be  the 
case  if  no  inversion  took  place,  for  in  the  latter 
case  all  images  must  necessarily  OQCWYty  2i  much  smaller 
place  upon  the  retina  than  the  size  of  the  jyujnl. 

Color  is  analagous 
to  pitch,  violet  corre- 
sponding to  the  high, 
and  red  to  the  low 
tones.     Intensity  of 
color,    as  of   sound, 
depends     upon    the 
amplitude      of     the 
vibrations.     "When  a  body  absorbs  all  the  colors  of  the 
spectrum  except  blue,  we  call  it  a  blue  body.     lied 
glass  has  the  power  of  absorbing  all  the  colors  except 


18  VETERINARY  OPHTHALMOLOGY. 

the  red,  which  it  transmits.  If  any  body  or  thing- 
reflects  all  colors,  we  have  white.  Should  all  the  colors^ 
be  absorbed,  we  have  black.  Light  travels  186,000  miles 
per  second  (discovered  by  Roemer  in  1676).  Scientific- 
ally this  is  of  great  moment,  but  to  us  the  rate  is  so 
great  that,  for  all  distances  on  earth,  it  is  instantaneous. 
The  globe  would  be  girt  by  a  sunbeam  quicker  than 
we  could  wink.  The  theory  of  to-day  as  regards  light 
is  the  undulatory  theory.  The  earth  is  supposed  to  be 
bathed,  embalmed,  enveloped  by  a  fluid  termed  Ether, 
which  is  very  subtle.  Suppose  a  luminous  body  sets 
in  motion  waves  of  this  Ether  which  go  in  every  direc- 
tion, moving,  remember,  at  the  rate  of  186,000  miles  per 
second.  Well,  these  waves  breaking  upon  the  retina 
cause  the  molecular  disturbance  termed  "  sight."  This 
wave  motion  is  like  that  of  sound,  except  that  the 
vibrations  are  transverse — cross-wise.  "  The  sunbeam 
comes  to  the  earth  as  simply  motions  of  Ether-waves, 
yet  it  is  the  grand  source  of  beauty  and  power.  Its 
heat,  light  and  chemical  force  work  everywhere  the 
miracle  of  life  and  motion.  In  the  growing  plant,  the 
burning  coal,  the  flying  bird,  the  glaring  lightning, 
the  blooming  flower,  the  rushing  engine,  the  roaring^ 
cataract,  the  pattering  rain,  we  see  only  varied  mani- 
festations of  this  one  all-energizing  force."  * 
*  Steele. 


CHAPTER  I. 
ORBITAL  CAVITY. 

Orbital  cavity. — According  to  Chauveau,  this  cavity 
is  irregularly  circular  in  outline  and  circumscribed  by 
the  orbital  process  of  the  frontal  bone,  the  lachrymal 


Fig.  13. 

and  malar  bones,  and  the  summit  of  the  zygomatic 
process.  At  the  bottom,  which  shows  the  maxillary 
and  orbital  hiatus,  it  is  confounded  in  the  skeleton 
with  the  temporal  fossa.*    It  lodges  the  globe  of  the 

*  A  fibrous  membrane,  the  ocular  sheath,  isolates  it  from  the 
temporal  fossa  in  the  majority  of  mammiferous  animals.     Only  in 
19    . 


20  VETEEINARY   OPHTHALMOLOGY. 

eye  and  the  muscles  which  move  it.  Some  organs 
accessory  to  the  visual  apparatus,  such  as  the 
lachrymal  gland  and  the  membrana  nictatans,  are  also 
contained  in  this  cavity.  The  temporal  fossa  sur- 
mounts the  orbit  and  is  incompletely  separated  from  it 
by  the  orbital  arch  (or  process).  Oval  in  shape,  lying 
obliquely  from  above  to  below,  and  from  within  out- 
wards, on  the  sides  of  the  cranium,  the  temporal  fossa 
is  limited,  within  by  the  parietal  ridge,  and  outwardly 
by  the  anterior  border  of  the  longitudinal  root  of 
the  zygomatic  process.  It  lodges  the  temporal 
muscle. 

The  orbital  cavity  is  situated  at  the  side  of  the 
head  at  the  point  corresponding  to  the  union  of  the 
cranium  and  the  face.  It  is  lined  by  a  fibrous  mem- 
brane, designated  the  ocular  sheath  (ocular  membrane 
or  periorbita),  which  is  attached  posteriorly  to  the  bor- 
der of  the  orbital  hiatus  and  anteriorly  to  the  upper 
lip  of  the  orbit,  being  prolonged  beyond  the  exteinal 
lip  of  this  osseous  rim  to  form  the  fibrous  mem- 
brane of  the  eyelids.  Strong  externally,  the  ocular 
sheath  is  thin  within  the  cavity,  composed  of  elastic 
and  inelastic  fibers  (unstriped  muscular  fibers  have 
also  been  included  in  its  composition),  traversed  by 
vessels  and  nerves.  Thus  completed,  the  orbital  cavity 
lias  the  form  of  a  regular  hollow  cone,  open  at  its  base, 

man  and  the  quadrumana  has  the  orbital  cavity  complete  bony 
walls. 


VETERINAEY   OPHTHALMOLOGY.  21 

closed  at  the  apex,  which  corresponds  to  the  orbital 
hiatus.  In  the  ordinary  position  of  the  head  the  open- 
ing of  this  cone  is  directed  forward,  downward  and 
outward.  The  bones  which  go  to  make  the  orbital 
cavity  are  the  frontal,  sphenoid,  superior  maxillary, 
malar,  palate,  ethmoid  and  lachrymal.  The  optic  for- 
amen, situated  at  the  apex  of  the  cone,  transmits  the 
optic  nerve  and  ophthalmic  artery.  The  superior  orbi- 
tal fissure  transmits  the  third,  fourth  and  sixth  nerves, 
ophthalmic  branch  of  the  trigeminus  and  the  superior 
and  interior  ophthalmic  veins.  The  inferior  orbital 
fissure  gives  passage  to  the  malar  and  infra-orbital 
nerves,  and  a  facial  branch  of  the  ophthalmic  vein. 
(See  Fig  41.)  The  supra-orbital  notch,  at  the  upper 
and  inner  margin  of  the  orbit,  contains  the  supra- 
orbital nerves  and  artery  as  they  pass  to  the  forehead. 
In  addition  to  the  bulbus,  muscles,  vessels,  etc.,  the 
orbit  contains  much  adipose  tissue. 

There  is  a  limiting  membrane  between  the  globe  and 
conjunctiva  and  the  cellulo-fatty  tissue,  called  Tenon's 
capsule.  To  some  extent  it  ensheaths  the  muscles, 
nerves  and  vessels  that  pass  through  it,  and  is  con- 
tinuous with  the  periosteum  of  the  orbit,  as  Avell  as 
with  the  conjunctiva.  It  is  somewhat  analogous  to  the 
pleura,  and  serves  as  a  cup  in  which  the  globe  revolves. 
It  constitutes  a  secondary  attachment  for  the  ocular 
muscles.  The  dura  mater  is  firmly  attached  at  the 
sphenoidal  fissure  and  optic  foramen,  and  is  continuous 


22  VETERINARY   OPHTHALMOLOGY. 

with  the  outer  sheath  of  the  optic  nerve  and  with  the 
periosteum  of  the  orbit. 

OrMtal  cellulitis. — Diseases  of  the  orbit  may  be  either 
simple  oedematous  cellulitis  or  phlegmonous  cellulitis. 
In  the  oedematous  form  there  will  be  bulging  forward 
of  the  bulbus.  Little  pain  on  pressure  occurs  in  the 
young  and  subsides  in  a  few  days.  The  phlegmonous 
form  is  much  more  severe ;  swelling  of  the  lids, 
especially  the  upper ;  pain,  which  may  be  intense  and 
will  tolerate  no  pressure  on  the  globe ;  eye  is  pro- 
truded directly  forward. 

Exophthalmus. — In  some  severe  cases  have  abso- 
lutely no  motion;  *  will  have  cheraosis  of  conjunctiva; 
symstoms  almost  always  acute,  and  the  crisis  is 
reached  in  8  to  14  days.  Tissues  on  palpation  will  be 
found  firm,  tense  and  hard.  All  this  may  go  on,  the 
bulbus  become  involved  and  have  inflammation  of 
all  parts  of  the  eye—jxoiojyhthalmitis.  When  pus 
forms,  as  it  may,  fluctuation  may  be  found  behind  the 
lids.  Abscess  may  burst  through  conjunctiva  or  lids. 
May  result  from  injuries,  periostitis  and  inflammation, 
of  lachrymal  gland. 

Treatment. — Antiphlogistics  early.  Should  sup- 
puration occur,  poultices  and  incision  through  conjunc- 
tiva between  the  lids.  Exploration  is  good  when  in 
doubt,  and  better  to  use  knife  too  early  than  too  late. 
A  large  majority  of  these  cases  recover,  and  about  the 

*  Compare  periostitis. 


VETERINARY   OPHTHALMOLOGY.  23 

only  untoward  results  are  abscess  of  brain  and  menin- 
gitis. Don't  be  fooled,  when  the  whole  thing  may  be 
a  simple  foreign  body,  the  removal  of  which  will  dis- 
sipate the  alarming  symptoms. 

Periostitis  of  the  Orbit  is  generally  limited  to  the 
margin  of  the  orbit.  It  may  arise  idiopathically  in  the 
rheumatic.  Some  swelling  and  redness  of  the  lids  and 
a  slight  exophthalmus,  generally  to  one  side.  Some- 
times slight  elevation  of  temperature.  Pus  may  form 
beneath  the  periosteum.  In  the  chronic  form  there  is 
simply  slight  swelling  of  the  upper  lid  and  supra-orbi- 
tal pain,  and  a  little  local  swelling.  This  form  is  very 
tedious,  running  months,  and  ending  in  caries,  deformi- 
ties, etc. 

Treatmext. — As  in  cellulitis.  If,  however,  it  has 
gone  on  to  necrosis,  etc.,  the  chisel  and  gouge  come 
into  play,  and  a  thorough  removal  of  and  curetting  is 
applied  to  the  carious  parts. 

Tumors  of  the  Orbit. — Both  benign  and  malignant. 
May  develop  primarily  in  the  orbit  or  spread  from  the 
face.  Cause  more  or  less  exophthalmus  and  its  conse- 
quences. 

Treatmext  is  excision.  Sometimes  it  is  necesary  to 
remove  bulbus  also :  {Eneucleation.) 


CHAPTER  II. 

EYELIDS. 

The  eye  is  protected  and  covered  by  two  mem- 
branous, movable  curtains — tlie  palpebrse — superior 
and  inferior.  Tliey  serve  to  protect  the  eye  and  to 
exclude  excessive  light.  Another  function  is  to  secrete 
and  distribute  a  moisture  to  the  eye.  Their  movements 
are  both  voluntary  and  involuntary,  the  involuntary 
due  to  the  orbicularis  muscle.  The  levator  palpebrse 
superioris  opens  the  eyes  by  lifting  the  upper  lid.  The 
space  between  the  free  margins  of  the  lids  is  the  pal- 
pebral fissure.  The  angles  of  junction  between  the  lids 
are  the  canthi,  the  external  being  the  most  acute.  At 
the  inner  canthi  are  found  two  small  elevations,  one  on 
each  lid — the  lyunctum  lachrymale — which  are  the  be- 
ginnings of  the  canals,  or  canaliculi.,  letiding  to  the  tear 
sac.  The  eyelids  are  composed  of  four  layers  :  (1)  the  in- 
tegument, (2)  layer  of  muscular  fibers,  (3)  the  tarsus,  and 
(4)  the  conjunctiva.  The  muscular  fibers  consist  of  the 
orbicularis  palpebrarum,  a  wide,  thin  sphincter  common 
to  both  lids,  having  tendinous  attachments  at  the  angles 

of  the  lids,  the  tendons  together  with  some  muscle- 
24 


VETERINARY   OPHTHALMOLOGY. 


25 


Fig.  14. 
Saggital  Section  through  the  upper  eyeUd.  1,  skin  ;  2,  palpebral  portion 
of  the  musculus  orbicularis  oculi ;  2a,  its  inner  portion,  designated  a8 
the  musculus  ciliaris  Riolini ;  3,  cilia;  4,  gland  of  Moll,  opening  into  a 
hair  follicle  ;  5,  Meibomian  gland  ;  5  a,  its  orifice ;  6,  indication  of  the 
ill-defined  limit  of  the  tarsus  ;  7,  loose  connective  tissue  between  tarsus 
and  anterior  insertion  of  the  tendon  of  the  musculus  levator  palpebrae 
superioris  ;  8,  anterior  eonnective-tissue-like  insertion  of  the  tendon  of 
the  musculus  levator  palpebrae  superioris  :  9.  its  middle  layer,  non- 
muscular,  called  the  musculus  palpebralis  superior.— JS^.  Muller. 


26  VETERINARY   OPHTHALMOLOGY. 

fibers  being  attached  to  the  bony  wall.  There  are 
certain  bundles  of  the  orbicularis  fibers— involuntary 
— known  as  the  ciliary  muscle  of  Hiolini.  The  orbicu- 
laris is  adherent  to  the  skin,  but  glides  smoothly  and 
loosely  over  the  tarsus.  The  contraction  of  this  muscle 
closes  the  palpebrse. 

The  Levator  PaJpehrm  Sux>erioris  arises  at  the 
orbital  apex,  passing  along  the  upper  wall,  becoming 
intermingled  with  the  orbicularis  in  front  of  the  tarsus. 
Some  fibers  go  to  the  conjunctiva,  while  some  become 
attached  to  the  upper  edge  of  the  tarsus.  Supplied  by 
the  motor-oculi.  Function  to  raise  the  lid.  The  lower 
lid  is  supplied  by  a  prolongation  from  the  inferior 
rectus. 

The  Tarsi. — The  framework  of  the  lids,  being  united 
together  and  to  the  adjacent  bone  by  the  internal  and 
external  lateral  ligaments,  gives  rigidity  and  stabil- 
ity to  the  eyelids.  Composed  of  fibrous  condensed 
tissue. 

The  Shhi  adheres  intimately  to  the  orbicularis 
muscle ;  smooth  and  covered  with  numerous  fine  short 
hairs.  In  the  foetus,  at  the  orbital  arch,  where  the 
skin  everywhere  else  is  without  hair,  we  find  a  well 
marked  eyebrow.  Fat  is  never  found  beneath  this 
skin. 

The  Conjunctiva  is  a  delicate  mucous  membrane, 
which  commences  at  the  free  border  of  the  lid  where  it 
is  continuous  with  the  skin.    It  lines  the  inner  surface 


VETERINARY    OPHTHALMOLOGY. 


27 


of  the  lids  and  is  reflected 
upon  the  globe,  over  which  it 
passes  and  becomes  con- 
tinuous  with  the  cornea. 
The  palpebral  portion  is 
thicker  and   more  vascular  ^^ 

than  the  ocular,  and  is  The  tarsi  seen  from  behind.  They 
have  been  isolated  from  other 
tissues  and  remain  joined  at  the 
external  and  internal  angles  by 
the  lateral  ligaments,  external 
and  internal :  1,  Posterior  surface 
of  tarsus  superior;  on  its  edge 
the  openings  of  the  Meibomian 
follicles;  2,  tarsus  inferior  ;  Sand 
4,  punctum  lachrymiale  superior 
and  inferior  ;  5,  external  angle  ; 
G,  internal  angle. 


firmly  attached  to  the  tar- 
sus. ^Yhere  it  passes  from 
the  lids  to  the  globe  it  is 
thin  and  very  loose  and 
forms  the  fornix  conjunctivce. 
Now,  as  its  name  indicates, 
it  joins  the  bulbus  and  pal- 
pebral together.  It  envelops,  in  addition  to  the  above, 
the  anterior  portion  of  the  haw  {memhrana  nictatcDis) 
ill  a  particular  fold,  and  covers  the  caruncula  lachry' 
malts  and  enters  the  puncta.  At  the  margin  of  the 
cornea  one  may  not  trace  it,  although  it  is  represented 
by  a  layer  of  pavement  epithelium.  At  the  surface  of 
the  caruncle  it  shows  some  very  fine  hair  bulbs.  (See 
conjunctiva.) 

Eyelashes  (cilia.) — Two  rows,  at  free  borders  of  the 
lids.  Act  as  a  shield  against  foreign  particles,  dust, 
etc.  Their  follicles  are  surrounded  by  sebaceous  glands 
and  the  glands  of  Moll  (which  are  small  tubular  glands 
resembling  ceruminous  glands.) 

These  various  glands  serve  to  lubricate  the  eye  by 


28  VETERINARY   OPHTHALMOLOGY. 

their  secretions,  which  emerge  by  minute  orifices  on 
the  free  border  of  the  lids.  The  lashes  are  longer  and 
stronger  and  more  abundant  in  the  upper  lid.  Though 
the  lashes  of  the  lower  lid  are  few,  they  are  reinforced 
by  some  long  bristly  hairs,  which  are  just  like  the 
tentacular  of  the  lips. 

The  Meibomian  Glands.— Analogous  to  sebaceous. 
They  are  lodged  near  the  posterior  surface  of  the  tarsus, 
arranged  like  currants  on  a  stem.  They  open  by 
minute  orifices  upon  the  free  border  of  the  lids  behind 
the  cilia.  Each  gland  consists  of  a  central  tube  with 
a  number  of  openings  around  its  sides.  The  unctuous 
matter  they  secrete  facilitates  the  retention  of  the  tears 
over  the  conjunctivse.  Supra-orbital,  lachrymal  and 
orbital  branch  of  the  superior  dental  arteries,  forming 
thick  network  indirectly  connected  around  the  cornea 
with  the  ciliary  system,  through  the  episcleral,  are  the 
arteries.  Lymphatics  form  a  close  network  around  the 
cornea.  Nerves  from  the  fifth  pair  enter  at  inner  and 
outer  angles  of  the  eye,  form  a  thick  plexus  and  end 
free— some  by  club-shaped  expansion.  These  nerve 
fibers  are  non-medullated, 

Membrana  Nictatans.— "  Third  or  winJcing  eyelid:'^ 
Hem.  At  the  inner  angle  of  the  eye.  Its  composition 
is  of  a  fibro-cartilaginous  framework,  elastic,  irregularly 
shaped,  prismatic  at  its  base,  which  is  thick,  and  thin 
anteriorly,  where  it  is  covered  by  the  conjunctiva. 
Behind  is  a  strong  cushion  of  adispose  tissue,  which  is 


VETERINARY   OPHTHALMOLOGY.  £9 

insinuated  betireen  all  the  muscles  of  the  eye.  The 
movements  of  the  haw  are  mechanical,  and  no  muscle 
directly  causes  them.  When  the  eye  is  in  repose  but 
a  small  fold  of  conjunctiva  is  seen;  the  rest  is  in  its 
fibrous  case.  When  the  eye  is  -withdravi^n  into  the 
orbit  by  contraction  of  the  recti  muscles,  the  globe 
compresses  the  fatty  cushion  belonging  to  the  carti- 
lage; this  cushion,  pressing  outwards,  pushes  the 
memhrana  before  it,  and  the  latter  then  entirely  con- 
ceals the  front  of  the  eye.  This  movement  is  instanta- 
neous, but  it  may  be  momentarily  fixed  by  pressing 
gently  on  the  eye  when  the  animal  retracts  it  within 
the  orbital  cavity.  The  use  of  the  membrana  is,  as  will 
be  seen  from  the  above,  to  maintain  the  healthy  con- 
dition of  the  eye  by  removing  any  matters  that  have 
escaped  the  eyelids;  and  what  clearly  demonstrates 
this  function  is  the  inverse  relation  that  always  exists 
between  the  development  of  this  body  and  the  facility 
with  which  animals  can  rub  their  eyes  with  their  ante- 
rior limbs ;  so  it  is  that,  with  the  horse  and  the  ox,  whose 
thoracic  member  cannot  be  applied  to  this  purpose, 
the  membrana  is  very  highly  developed,  and  in  the 
dog,  which  may  use  its  paw  to  some  extent  when  it 
requires  to  brush  its  eye,  it  is  smaller  ;  in  the  cat  it  is 
still  fess,  while  in  the  monkey  and  in  mankind,  whose 
hands  are  perfect,  it  is  rudimentary.  In  tetanus,  the 
membrana  nictatans  often  remains  permanently  over 
the  eye  in  consequence  of  the  continued  contraction  of 


30  VETERINARY   OPHTHALMOLOGY. 

the  recti  muscles.*  The  gland  of  Harder,  situated  on 
the  outer  face  of  the  haw,  is  a  reddish-yellow  gland^ 
covered  by  fibrous  membrane  and  surrounded  by  fat. 
Secretes  a  thick  unctuous  matter,  which  gains  exit  on 
the  inner  face  of  the  membrana  by  three  or  four  open- 
ings. 

DISEASES    OF    THE    LIDS. 

Acute  Blepharitis. — Abscess  of  the  lids.  Is  an  acute 
phlegmonous  inflammation  of  the  lids ;  usual  cause  is 
of  a  traumatic  nature.  May  accompany  strangles  or 
follow  it;  adenitis  simple.  Will  have  great  swell- 
ing with  the  cardinal  symptoms ;  apt  to  have  con- 
junctivitis accompany  this.  May  have  fluctuation 
early.  This  might  go  on  to  gangrene.  If  early  enough, 
cold  applications  to  abort.  If  later,  and  suspect  forma- 
tion of  pus,  hot  applications,  and  get  the  matter  over 
with.  Of  course,  as  soon  as  fluctuation  is  felt,  open 
freely  and  mahe  the  incision  parallel  with  the  lid  bor- 
der. Evacuate  freely,  using  antisepsis  and  ascepsis 
(and  Boric  acid  solution  is  good  and  safe  about  the 
eye)  for  patient  and  instruments.  Do  not  use  Hydrar 
for  instruments,  as  you'll  dull  the  edge  quicker  than  it 
can  be  restored,  and  not  more  powerful  than  1  to  5000 
about  the  eye,  unless  great  care  is  taken  to  prevent  its 
entrance  into  the  conjunctival  sac.  May  suture  if 
you  think  necessary ;  compress  bandage  to  insure  first 
intention. 

*  F.  Lecoq  in  Chauveau's  Anatomy. 


VETERINARY    OPHTHALMOLOGY.  31 

Blepharitis  Ciliaris  {Blepharitis  Marginalise  Tinea 
Tarsi^  Ophthalmia  Tarsi). — Rarely  met  with  in  equine 
patients,  but  when  it  is,  it  is  long-lasting  and  very  rebel- 
lious. This  may  be  merely  a  slight,  scarcely  perceptible 
redness  of  the  lid  margin,  while  again  it  may  be  very 
severe — ulcerations,  or  thickened  everted  edges. 
Caused  by  smoke,  dust,  cold  winds,  bright  light  and 
too  much  of  it.  Lids  are  apt  to  be  agglutinated.  Edge 
or  margins  scaly  and  scabby.  Photophobia  and  lachry- 
mation.  Hair  follicles  may  be  destroyed  and  the  cilia 
fall  out.  The  thickening  and  eversion  of  lids  may 
cause  ectropium. 

Always  assure  yourself  it  is  not  the  result  of  Phthe- 
iriasis,  for,  if  it  is,  it  will  be  necessary  to  eradicate  them 
before  attempting  a  cure  of  the  Blepharitis.  Use  Merc, 
■ung.  Fungus  growths  in  the  hair  follicles  are  also 
said  to  cause  this  disease.  Pemove  the  hairs  by 
epilation,  and  go  on  to  cure.  Lachrymal  catarrh,  and 
particularly  catarrh  of  the  lachrymal  sac,  with  stric- 
ture of  the  duct ;  the  tears,  unable  to  get  through  into 
the  nose,  flowing  over  the  lids.  Tears  being  retained, 
inflammation  ensues.  In  such  cases  ojien  the  cana- 
liculus into  the  sac  and  give  free  passage  for  the  tears, 
then  go  on  and  treat  as  a  simple  case.  It  is  very  neces- 
sary to  observe  cleanliness.  Removal  of  scales  and 
scabs — without  force.  If  can  not  get  them  away  easily, 
poultice  the  eyes  for  fifteen  or  twenty  minutes.  Then 
proceed:  Vaseline.    Boric  ac.  and  vaseline;  gr. — xxx. 


32 


VETERINAllY   OPHTHALMOLOGY. 


to  one  ounce ; — Oxide  of  zinc  ointment.  If  it  has  gone 
on  to  ulceration,  after  removing  the  crusts  gently,  use 
hydrar.  ox.  flav,  grs.  two  to  vaseline  one  dram ; — or  cit- 
ron ointment  x  or  xx  grs.  to  the  dram,  of  vaseline.  May 
cauterize  the  ulcers  with  a  fine  point  of  lunar  caustic. 

Stye  {Hordeolum).    Acute  inflammation  of  cellular 
tissue  of  the  lids,  with  suppuration  and  pointing  at  the 


Fig.  16.  Fig.  VI. 

edge  of  the  lids.  This  usually  is  found  around  a  hair 
follicle  and  first  appears  as  a  circumscribed  swelling. 
Some  cases  go  on  and  involve  the  entire  lid,  which  be- 
comes swollen  and  oedematous.  Much  severe  throbbing 
pain.  Often  multiply  and  may  return  in  successive 
crops.  Usually  break  in  a  week.  Some  are  absorbed 
and  do  not  break.    Incise  if  pointed,  and  evacuate. 


VETERINARY   OPHTHALMOLOGY.  33 

Will  just  mention  here  adroopinjjof  the  lid,  due  either 
to  partial  or  complete  paralysis  of  the  levator  palpebrse 
superioris.  Is  called  Ptosis.  If  you  should  desire  to 
correct,  remove  an  elliptical  portion  of  the  skin  and 
muscular  fibers,  and  suture.  (See  Figs.  16  and  17). 
There  is  another  condition  which  may  be  met  with, 
called  Blepharospasmtis^  and  it  is  a  spasmodic  closure 
of  the  lids.  May  be  due  to  a  foreign  body,  ulcus  corneae, 
iritis.  Carious  teeth.  May  be  tonic;  or  clonic,  lasting 
but  a  few  seconds  at  a  time,  liemove  the  cause  of  irri- 
tation, which  is  the  only  treatment.  Another  rarety, 
called  nictitation,  which  is  a  constant  blinking,  may  be 
due  to  some  irritation  in  the  eye,  or  of  a  reflex 
character,  from  worms,  decayed  teeth,  etc.  Remove 
cause. 

Blspharophimosis  is  a  narrowing  of  the  palpebral 
opening,  usually  the  result  of  chronic  trachoma,  and  can 
be  relieved  by  canthotomy,  performed  by  inserting 
blunt  pointed  scissors  in  outer  canthus  and  snipping  as 
far  as  desired. 

Trichiasis  and  Distichiasis. — The  fii'st  is  an  irregu- 
larity in  shape  and  disposition  of  the  cilia.  The  second 
is  a  double  row  of  cilia. 

Trkatmext  :  epilation. 

Entropium  is  an  inversion  of  the  eyelid,  spasmodic 

and  cicatricial.     First  usually  in  the  lower  lids ;  comes 

from  keratitis,  foreign  bodies,  etc.    Second  is  the  result 

of  granular  and  diphtheritic  conjunctivitis,  burns,  etc., 

3 


84 


VETERINARY  OPHTHALMOLOGY. 


•where  there  has  been  loss  of  substance  in  the  conjunc- 
tiva. In  the  spasmodic  form  may  use  adhesive  plas- 
ter ;  paint  with  collodion  and  keep  the  lid  in  position. 


Fig.  18. 

Represents  a  vertical  section  of  the  upper  eyelid.    S,  supra  orbital  margin  : 

to,  fascia  tarso-orbitalis  ;  po,  parsorbitalis  ;  pc,  pars  ciliaris  of  orbicularis 

muscle ;  t,  tarsus  ;   c,  eyelash  ;  f ,  lower  border  ;  d,  upper  border  of  the 

■wound  ;  a  b,  passage  of  suture  through  aponeurosis.— iVbi/es, 

In  cicatricial,  operative  interference  consists  in  re- 
moving a  slight  strip  of  skin  parallel  with  the  lid  mar- 
gin and  suturing,  entering  the  suture  on  the  conjunc- 
tival side  of  the  lid  and  drawing  the  lips  of  the  incision 
together.     This  will  evert  the  lid.    (See  Fig.  18.) 

Ectropium. —  E  version  of  the  eyelid  may  be 
slight  or  great.  Two  ioviins— cicatricial,  due  to  con- 
traction after  burns,  abscesses,  wounds,  etc. ;  conjimc- 
tival^  when  due  to  chronic  inflammation  and  swelling  of 
the  conjunctiva,  which  separates  the  lid  margin  from 


YETEEINAllY   OPHTHALMOLOGY. 


85 


Fig.   19. 


the  eye,sometimes  aided 
by  relaxation  of  the  skia 
'  and  spasm  of  the  orbicu- 
laris muscle.  The  best 
results  are  obtained  by 
the  removal  of  a  V- 
shaped  piece  of  skin,  and 
dissecting  it  aAvay. 
Bring  the  edges  together 
so  as  to  p?<s/i  and  sup. 
port  the  eyelid  in  its  pro- 
per position,  causing  the 
sutures  to  assume  a  Y- 
like  appearance.  This 
is  the  Wharton  Jones  operation.  (See  Figs.  19  and  20.) 
When  we  find  an  eyelid 
fast  to  the  eye-ball  the 
condition  is  known  as 
Sij7nhle2)/iaron.  Is  the  re- 
sult of  burns,  severe  in- 
flammations, such  as  con- 
junctivitis, or  anything 
Avhicli  will  cause  the  de- 
struction of  the  mucous 
membrane.  This  grow- 
ing together  may  be 
partial,  or,  we  should  say,  of  more  or  less  extent. 
For  instance,  the  entire    lid  may  be  adhered   to  the 


Fig.  J 


S6 


VETERINARY  OPHTHALMOLOGY. 


globe,  and  again  it  may  be  only  a  thread-like  attach- 
ment. The  treatment  is  to  separate  and  keep  apart  un- 
til the  parts  are  healed  over.  This  may  necessitate 
transplantation  from  other  portions  of  the  globe,  or 
borrow  from  a  rabbit's  eye.  An  adhesion,  growing 
together,  of  the  lid  margins,  is  Anchylohlepharon,  com- 
plete or  partial. 

Treatment  is  division.  (See.  Fig.  21.) 
Chalazion  is  obstruction  of  some  of  the  follicles 
of  the  tarsus  with  re- 
tention of  its  secretion. 
The  diagnostic  point  is 
that  the  skin  is  freehj 
movable  over  it.  Vary 
in  size,  and  are  apt  ta 
come  in  crops.  Fluctua- 
tion is  never  felt.  Ex- 
cision is  the  treatment. 
Make  the  primary  incision  on  the  skin  ^wxh^Q^— parallel 
to  the  lid  border.  May  open  on  the  inside  if  it  points 
that  way.  This  has  a  sac  wall,  remember,  which  must 
be  either  removed  or  tlioroughhj  scraped,  curetted, 
spooned  out.  Cocaine  will  be  the  only  anaesthetic 
needed,  dropping  some  of  a  4  per  cent,  solution  into 
the  conjunctival  sac  and  hypodermically  injecting  some 
alongside  the  tumor,  which  will  render  the  operation 
nlmost  painless.  May  lightly  touch  with  lunar  caustic 
to  insure  healing.      All  operations  upon  the  lids  are 


Fig  21 


VETERINARY    OPHTHALMOLOGY.  37 

productive  of  free  hemorrhages,  which  may  be  very 

successfully  controlled  by  using  a  clamp  such  as  this. 

Contusions  should  be  treated  as  contusions  elsewhere. 


Fig.  22. 


Immediately  after  a  contusion,  cold  compresses,  firm 
bandaging,  cooling  and  soothing  lotions,  etc. 

Burns  and  Scalds.— The  great  care  is  prevention 
of  adhesions.  If  lime  is  the  burning  cause,  antidote 
it  immediately  with  acids,  vinegar,  etc.,  or  protect  with 
oil,  freely  used.  Do  not  wash  out  the  conjunctival 
sac  unless  you  hviVQ  plenty  of  water.  A  small  amount 
would  but  aggravate  the  condition  by  slaking  the  lime. 

Wounds. —Treat  as  elsewhere;  cleanliness, antisepsis. 
Carefully  inquire  into  the  condition  of  the  parts  sever- 
ally and  as  a  whole.  Careful  coaptation  of  the  wound's 
lips,  intelligent  suturing,  and  watch  out  for  adhesions 
always. 


CHAPTER  III. 

THE  LACHRYMAL  GLAND. 

Laciirymal  Gland. — Situated  between  the  orbital 
process  and  upper  part  of  the  eyeball  and  close  to  its 
interior  margin,  convex  superiorly,  concave  inferiorly. 
Is  an  acinous  gland,  formed  of    small  granulations, 


Fig.  23. 


whose   junction  forms   ducts  called   hygrophthalmic 
canals.    These  run  to  the  upper  and  outer  portion  of 


38 


VETEEINAEY   OPHTHALMOLOGY.  39 

the  superior  fornix  of  the  conjunctiva.  Secretion  is 
alkaline,  moistens  anterior  surface  of  the  eye,  passing 
off  by  means  of  the  puncta,  canaliculi,  lachrymal  sac 
and  nasal  duct  to  the  nose.  The  puncta  are  two 
openings  of  the  canaliculi,  at  the  inner  canuhus,  a  short 
distance  from  the  commissure.  Function,  to  collect  the 
tears.  The  canaliculi  extend  from  the  puncta  to  the 
lachrymal  sac,  and  these  canaliculi  join  before  reach- 
ing the  lachrymal  sac.  The  lachrymal  sac  is  the 
upper  dilated  portion  of  the  nasal  duct,  which  is  situ- 
ated in  a  groove  or  osseous  canal  in  the  lachrymal  bone. 
Terminates  between  the  two  turbinated  bones.  The 
balance  of  the  canal  is  under  the  nasal  mucous  mem- 
brane, passes  to  inner  surface  of  outer  wing  of  the 
nostril,  terminating  by  an  orifice  (sometimes  two) 
toward  the  lower  commissure,  where  the  line  of  de- 
marcation between  the  skin  and  rosy  mucous  mem- 
brane presents. 

The  tears  are  forced  into  the  excretory  passage  by 
muscular  action  and  some  kind  of  suction  caused 
by  the  muscular  fibers  of  the  puncta  and  canali- 
culi. 

Dacryoadenitis. — Very  rare  indeed.  Symptoms  of 
the  acute  form  are  great  swelling  and  redness  of  the 
upper  lid  at  its  outer  angle.  The  gland  will  be  pushed 
out  of  its  fossa  downwards,  by  the  inflammation  and 
swelling,  and  may  be  recognized  on  everting  the  lid. 
The  swelling  may  be  so  great  as  to  displace  the  globe 


40  VETERINARY   OPHTHALMOLOGY. 

down  and  inward.  Suffering  is  pronounced.  May- 
have  an  accompanying  conjunctivitis,  chemosis,  etc. 
Sometimes  confounded  with  periostitis.  May  have 
suppuration.     Generally  of  traumatic  origin. 

Treatment — If  early,  ice  may  abort.  So  soon,  how- 
ever, as  there  is  suppuration,  aid  the  formation  with 
heat.     Free  incisions  through  the  conjunctiva. 

Dislocation  of  the  gland  has  been  seen  and  hyper- 
tropliij  of  the  gland  is  exceedingly  rare.  This  struc- 
ture may  be  the  seat  of  new  growths,  as  glandular 
structures,  in  other  parts  of  the  bodj'^,  and  should  be 
treated  as  elsewhere,  i.  e.,  extirpation  of  entire  gland. 


CHAPTER  IV. 

EXCRETORY  APPARATUS. 

Excretory  Apparatus  (Diseases  of). — As  a  result  of  in- 
flammations ;  of  the  conjunctiva  and  lids ;  wounds  of 
the  lid;  narrowing  and  stoppage  of  the  canaliculus; 
may  have  watering  of  the  eye  (Fpiphora).  If  ob- 
struction of  the  canaliculus,  slittiiig  the  canal  with  a 
knife  modeled  by  and  bearing  the  name  of  Agnew  is 
the  treatment.    This  is  a  narrow-bladed,  probe-pointed 


A;::C-.v's  Canaliculus  Knife 
Fig.  24. 

knife.  Enter  the  puncta  with  its  probe  point,  verti- 
calhj.  Remember  the  anatomical  disposition  of  the 
canaliculus  in  the  angle  of  the  lid  M\i\.foUoio  it.  The 
idea  is  to  open  the  already  existing,  but  obstructed 
passage,  and  not  to  establish  a  new  one.  "When  entered 
vertically,— and  that  takes  patience,  but  the  sphincter 
will  yield  to  persevering  pressure — depress  the  handle 
of  the  knife  until  it  is  horizontal.  Push  immrd  until 
you  reach  the  inner  wall,  keeping  the  lid  on  the 
41 


42  VETEEINAEY   OPHTHALMOLOGY. 

stretch.  Bring  the  knife  straight  up  and  down  and 
cut  the  whole  length  of  the  canaliculus.  This  is  diia- 
cultof  accomplishment  in  the  horse,  owing  to  the  length 
of  the  canal ;  but  a  knife  with  a  malleable  shank  will 
facilitate  matters  much.  Remember  and  divide  the 
canaliculus  close  to  the  juncture  of  skin  and  mucous 
membrane,  so  that  its  function  of  collecthig  the  tears 
may  be  as  little  interfered  with  as  possible,  close 
coaptation  to  the  conjunctiva  being  one  of  the  factors 
of  that  important  function. 

Strictura  of  the  Lachrymal  Duct.— Most  common  of 
all  the  lachrymal  affections.  Its  one  symptom  is  a 
flowing  of  tears— Epiphora.  May  be  result  of  catarrh, 
trauma,  carious  teeth,  pressure  from  tumors,  and  peri- 
ostitis. 

Dacryocystitis  Catarrhalis. — Seldom  recognized  be- 
fore the  chronic  stage.  Practically  no  difference  be- 
tween this  and  catarrh.  Will  find  a  swelling  at  the  in- 
ner angle  of  the  eye,  caused  by  a  retention  of  secretion 
from  the  catarrhal  inflammation,  and  swelling,  lessening 
the  caliber  of  the  excretory  ducts.  Firm  pressure  on 
this  swelling  will  cause  mucous  to  flow  from  either 
the  canaliculus  or  down  the  duct,  into  the  nasal  cavity. 
The  swelling  is  generally  painless.  Keeping  the  sac 
empty  affords  some  relief.  Have  generally  a  coexist- 
ing blepharitis  marginalis.  The  secretion  after  a  time 
becomes  irritating,  and  this  is  especially  the  case  when 
it  is  permitted  to  remain  quiet  some  time  in  the  sac. 


VETERINARY   OPHTHALMOLOGY. 


43 


Then  it  sets  up  conjunctivitis.  It  becomes  infectious, 
and  if  it  gain  entrance  to  a  wound  of  tlie  cornea  is  apt 
to  cause  suppuration.  In  diagnosing,  the  question  of 
tears  decides.  For  instance,  the  tumor  will  be  lessened 
by  pressure  and  the  contents  come  upwards  through 
the  puncta  or  descend  to  the  nose.  This  might  be  the 
result  with  a  very  tight  stricture,  but  of  less  degree, 
or  the  sac- walls  may  be  very  thick,  but  remem- 
ber the  tears — Epiphora — and  that  is  decisive.  These 
conditions  are  rebellious — may  continue  for  months. 
The  cure  of  the  underlying  catarrh  is  imjierative.  Any 
cause  must  be  removed.  Strictures  must  be  dilated. 
May  have  to  precede  dilation  by  slitting  the  canalic- 
ulus, but  dont  slit  the  puncta  if  can  avoid.  Take, 
by  preference,  a  pair  of  fine  iridectomy  forceps,  and, 
gently  insinuating  the  closed  points  into  the  puncta, 
dilate  the  s[)hincter  until  it  i-elaxes,  and  will  then  be 
able  to  introduce  a  small  probe   (Bowman's).     Then 


Bowman's  Set  of  Probes,  Kos.  1. 2.  3.  4,  5,  6.  7.  8. 

Fig.  25. 

introduce  a  Stilling's  knife  and  slit  the  stricture,  using 


JICMANNzr.O 

Fig.  36. 


44  VETERINARY   OPHTHALMOLOGY. 

same  method  as  in  probing.  This  knife  being  tri- 
angular, after  introduction  it  is  simply  necessary  to 
turn  it  in  different  directions  and  force  it  down  two 
or  three  times.  Blood  issuing  from  the  nose  is  proof 
of  an  open  passage.  In  some  instances  it  is  impossible 
to  gain  entrance  into  the  canaliculi  without  nicking 
the  puncta,  but  remember  that  you  are  apt  to  destroy 
the  normal  function  of  the  parts,  impairing  its  suction 
powers.  Electrolysis  has  produced  good  results — in- 
troducing a  probe  until  reaching  the  stricture  and  at- 
taching the  negative  pole ;  apply  the  positive  to  the  tem- 
ple and  make  gentle  pressure  as  the  stricture  yields. 
Repeat  this  until  permanent  results  are  achieved. 

Lotions  on  the  lids,  astringents  to  the  conjunctiva, 
are  good.  Arg.  nit.  gr.  v  to  31.  Watch  and  treat  the 
nasal  catarrh.    Dobell's  sol.  is  nice  and  successful. 

]J .  Sod.  bibor.,  3  iv. 

Glyc,   3i. 

Sod.  bicarb., 

Ac.  carb.,  aa  §  ss. 

Aq.,  3vi. 

If  this  condition  continues,  becomes  phlegmonous,  it 
is  called  Dacryocystitis  Phlegmonosa.,  and  is  a  higher 
stage  of  the  preceding.  Have  much  swelling  and  ex- 
treme sensibility.  Usually  much  infiltration  of  the  sur- 
rounding parts.  Constitutional  symptoms  very  often. 
Conjunctiva  may  be  inflamed  and  even  chemosed. 


VETERINARY   OPHTHALMOLOGY.  45 

Must  differentiate  between  this  and  abscess  of  the 
cellular  tissue.  In  abscess,  pressure  will  not  reduce 
it,  while  in  dacnjocystitls  iMegmonosa  the  contents 
will  be  forced  througli  the  puncta  or  down  into  the  nose. 
And  remember  the  previous  history  of  long  lachryma- 
tion. 

Treatment  is  incision  into  the  sac,  and  in  ad- 
vanced cases  (which  are  the  only  ones  you  will  meet) 
this  is  the  only  treatment.  Thrust  the  knife  per- 
pendicularly down  to  the  bone  and  carry  the  incision 
down  as  far  as  necessary.  Keep  the  incision  open 
with  lint.  If  it  has  opened  spontaneously,  poultice 
for  twenty-four  hours,  but  not  too  long;  maybe  forty- 
eight  hours  of  hot  poulticing,  but  no  longer.  After 
this  opening  has  closed  it  will  be  necessary  to  open  the 
nasal  duct  and  establish  a  passage  for  tears.  Don't 
probe  until  subsidence  of  inflammation. 

Lachryinal  Fistula. — Result  of  an  illy-healed  abscess, 
and  indicates  the  existence  of  a  permanent  stricture. 
Rarely  seen.  If  possible,  the  re-establishment  of  the 
proper  channel  for  the  passage  of  tears  should  be  the 
primary  care.  Then  the  fistula  can  be  easily  healed, 
treating  as  you  would  a  sluggish  fistula  anywhere, 
stimulating  its  edges  with  lunar  caustic,  etc. 


CHAPTER  V. 


MUSCLES  OF  THE  EYE. 


Muscles  of  the  Eye. — Seven — loosterior,  superior,  in- 
ferior, external  and  internal  recti,  and  superior  and  in- 
ferior oblique. 

Posterior  Rectus  Rectractor  Oculi,  as  its  name  implies, 
pulls  the  bulbus  backward.    Is   a  muscular  sheath,. 


Fig. 


with  fibers  disposed  longitudinally ;  arises  from  around 
the  optic  foramen  and  inserted  into  the  posterior  part 
of  the  external  face  of  the  sclerotic.  May  be  dissected 
into  four  bundles.   Superior^  Inferior^  External^  andln- 


46 


VETERINARY   OPHTHALMOLOGY. 


47 


temal  recti.    These  are  placed  upon  the  posterior  rectL 
Each  is  a  flat  band  with  parallel  fibers.    Origin  at  the 


S.lni 


Fig.  aa 

Scheme  of  the  action  of  the  ocular  muscles.— Landow. 

back  of  the  ocular  sheath  aud  inserted  into  the  sclero- 
tic, by  an  aponeurosis.    These  muscles  are  separated 


48  VETERIKARY   OPHTHALMOLOGY. 

from  one  another  and  the  posterior  by  the  fat  belong- 
ing to  the  membrana  nictatans.  They  act  according 
to  position,  and,  as  I  have  demonstrated  upon  the  board, 
according  to  concerted  action. 

Superior  Oblique,  or  Great  Oblique. — This  arises 
from  the  back  of  the  orbit  and  passes  forward  against 
the  inner  wall  to  pass  through  a  strong  flbro-cartilag- 
inous  pulley,  which  is  attached  to  the  frontal  bone  at 
the  base  of  the  orbital  process ;  then,  bending  out- 
ward, passes  beneath  the  superior  rectus  neaiiits  at- 
tachment and  inserts  itself  into  the  sclerotic  between 
the  superior  and  external  rectus.  Consequently  this 
muscle  pivots  the  eye  inward  and  upward,  carrying 
the  outer  aspect  of  the  globe  upwards  and  its  lower 
part  outwards. 

Inferior  or  Small  Oblique  Muscle. — Thicker  and 
shorter  than  the  superior;  is  nearly  parallel  to  the 
reflected  portion  of  the  superior.  Arises  in  the  lachry- 
mal fossa,  passes  outward  and  is  inserted  in  the 
sclerotic  between  the  external  and  inferior  recti.  In 
action  it  antagonizes  the  great  oblique.  The  move- 
ments of  the  bulbus  correspond  to  a  ball  and  socket 
joint.  The  center  of  rotation  is  a  short  distance  be- 
hind the  center  of  the  eye. 

The  oculo-motor  nerve,  or  third  pair,  supplies  all  the 
muscles  of  the  eye  except  the  external  rectus  and  supe- 
rior oblique,  which  are  supplied  by  the  sixth  and  fourth 
pair  respectively.    These  muscles  are  susceptible  to 


VETERINARY   OPHTHALMOLOGY.  49 

paralysis,  individually  and  collectively.  When  indivi- 
dual muscles  are  affected  we  find  restricted  motion^ 
converse  to  the  action  of  the  muscle  when  physiolo- 
gically exerted.  If  complete  paralysis  of  the  third  pair 
occurs,  then  have  ptosis,  some  exophthalmus,  ditto 
dilatation  of  the  pupil  and  accommodation  paralyzed. 
Movements  restricted  in  all  directions,  except  directly 
outward. 

Strabisimus  or  Squint-Many  varieties.  Usually 
mono-lateral,  which  is  a  faulty  position  of  one  eye.  May 
be  alternating-the  ability  to  fix  with  either  eye. 
Also  have  intermittent  or  constant. 

Treatment  is  operative;  divide  the  tendon  of  the 
contracting  muscle. 


4 


CHAPTER  VI. 

THE  CONJUNCTIVA. 

Conjunctiva. — A  delicate,  fine  mucous  membrane ; 
lines  the  inner  surface  of  the  lids.  From  the  lids  it  is 
reflected  upon  the  bulbus  and  extends  to  the  cornea, 
covering  the  sclerotic.  It  is  continuous  with  the 
cornea.  Consists  of  three  layers — external  being- 
epithelial,  the  intermediate  being  the  proper  tissue  and 
tbe  subconjunctival  tissue.  The  palpebral  conjunc- 
tiva especially  contains  numerous  lymphatics  and 
glandular  structures.  The  conjunctiva  in  its  reflec- 
tion from  lid  to  bulbus  forms  the  cul-de-sac  or  fornix. 
Highly  supplied  with  nerves  from  the  fifth  pair  (tri- 
geminus). Also  well  furnished  with  blood,  and  especi- 
ally so  around  the  limbus.  The  conjunctiva  has  the 
important  function  of  luhrication.  The  membrane  is 
divided  into  three  distinct  portions :  Tarsal,  which  is 
smooth,  and  fits  the  tarsi  (the  Meibomian  follicles  may 
be  seen  through  it)  the  fornix,  sinus  and  cul-de-sac 
being  the  reverse,  loosely  attached  and  easily  mov- 
able, and  is  dark  in  color,  while  the  tarsal  is  of  a  light 
yellow;  and  third,  the  ocular  portion  which  lies  loosely, 

but   smoothly,  upon  the  globe,  and  this  fact  aids  in 
50 


Veterinary  oPHTHAXMOL-aGY.  51 

diagnosing  between  conjunctivitis  and  inflammations 
•of  a  deeper  nature. 

Conjunctivitis  Catarrhalis. — Pxirxdent  (which  may 
be  idiopathic  or  gonorrheal,  JDiphtheretic^  Granular^ 
Phlyctenular^  these  are  some  of  the  forms  of  inflam- 
mation of  the  conjunctiva,  one  of  which  may  run  into 
another.  The  discharge  from  one  kind  may  reproduce 
itselt  or  one  of  another  form.  They  are  contagious 
and  infectious.  May  occur  epidemically.  Pink-eye  is 
but  an  epidemic  catarrhal  conjunctivitis.  A  differentia/ 
diagnosis  is  often  impossible  early. 

Catarrhal  Conjunctivitis. — Catarrhal  ophthalmia  is 
the  mildest  form.  Caused  by  injuries,  exposure,  bad 
hygiene,  exanthematous  diseases,  etc.  Again,  it  may  be 
secondary  to  other  inflammations.  Among  the  symp- 
toms we  find  smarting  preceded  by  itching,  lachryma- 
tion,  sensation  of  sand  or  of  some  other  foreign  body 
in  the  eye.  Have  increased  vascularity,  causing  partial 
or  uniform  redness  of  the  ocular  conjunctiva  and  impart- 
ing to  the  palpebral  conjunctiva  a  velvety,  roughened  ap- 
pearance. CEdematous  swelling  of  the  conjunctiva  and 
subjacent  tissue,  which  may  go  on  to  chemosis,  causing- 
the  cornea  to  look  sunken.  Redness,  swelling  and  stiff- 
ness of  the  lids.  Mucus  or  muco-purulent  discharge, 
with  tendency  toward  agglutination  of  the  lids,  espe- 
cially succeeding  sleep.  Both  eyes  usually  participate, 
although  one  eye  may  go  free.  This  form  is  amenable 
to  treatment  and  not  very  apt  to  invade  the  cornea. 


62  VETERINARY   OPHTHALMOLOGY, 

Now,  when  the  front  of  the  eyeball  is  red,  it  is  impor- 
tant to  know  whether  the  congestion  is  superficial  or 
deep.  If  superficial,  the  redness  will  he  conjunctival 
and  will  appear  as  a  coarse  network  of  blood  vessels, 
running  over  the  sclerotic  very  irregularly  and  in  no 
order  at  all,  or  by  a  more  uniform  redness  which, 
nearly  conceals  all  the  white  of  the  globe.  If  the  con- 
gestion and  swelling  are  not  very  great,  the  edge  of 
the  lower  lid  rubbed  against  the  globe  by  the  finger 
may  be  seen  to  move  the  vessels  over  the  sclerotic  and 
to  press  the  blood  out  of  them.  The  inner  surface  of 
the  lids  will  be  congested  also,  and  there  will  be  a 
mucous  or  muco-purulent  discharge,  with  probably  not 
very  much  photophobia.  In  deep,  or  ciliary  conges- 
tion, there  is  a  rosy  zone  of  straight,  fine  vessels,  as  I 
here  draw  upon  the  blackboard,  and,  as  you  see,  resem- 
bling the  rays  of  a  brilliant  sun.  Very  regular,  straight 
as  an  engraver's  lines,  totally  different  from  conjuncti- 
val injection,  which  is  highly  irregular  and  of  a  grape- 
vine order.  These  straight  fine  lines  nxdinte  from  the 
corneal  margin.  They  are  immovable  under  press- 
ure through  the  lower  lid,  while  the  conjunctival,  re- 
member, are  movable,  and  the  blood  may  be  pressed 
out  of  them.  On  close  inspection  the  rosy  zone  is  seen 
to  lie  beneath  the  conjunctiva,  in  the  sclerotic.  When 
we  find  this  form  of  congestion,  although  it  may  be 
very  slight,  there  will  be,  usually,  pain,  photophobia 
and  profuse  lachrymation,  and  the  tears  will  be  hoU 


VETERINARY   OPHTHALMOLOGY.  53 

This  picture  indicates  ciliary  irritation  and  an  affection 
of  the  cornea  or  of  some  of  the  deeper  structures.  Of 
course  the  two  kinds  of  congestion  are  often  found  com- 
bined. When  the  exit  of  venous  blood  from  the  interior 
of  the  eye  is  impeded,  large  dark,  tortuous  veins  will 
appear  running  over  the  sclerotic,  which  they  penetrate 
near  the  edge  of  the  cornea.  It  is  important  to  learn, 
in  the  presence  of  inflammation,  as  to  the  existence  of 
pain,  tenderness  in  the  ciliary  region,  which  is  the  name 
given  that  region  immediately  surrounding  the  cornea. 
To  this  end,  make  gentle  pressure  over  the  closed  lids' 
about  this  region  using  the  index  finger  of  each  hand 
and  palpating,  as  if  for  suspected  abscess,  for  instance." 
Examinations  are  somewhat  difficult  owing  to  the 
photophobia.  Will  be  facilitated  by  a  drop  or  so  of 
cocaine  4%.  Use  oblique  illumination,  as  I  have  de-' 
monstrated  in  the  clinic.  Notice  the  mobility  of  the 
pupil  and  intra-ocular  tension.  ' 

Tkeatmext:  extreme  cleanliness,  hygienic  precau- 
tions, attention  to  general  health.  Topically,  some 
mild  astringent  lotion  every  few  hours.  A  caustic  ap- 
plied at  the  outset  may  abort.  Cold  applications  in  the 
early  stages  are  very  good  ;  catarrhal  conjunctivitis  is," 
however,  a  self-limited  affair,  which  often  requires  very 
little  local  treatment,  and  which,  with  good  hygiene,  ter-' 
minates  in  complete  recovery.  However,  do  not  be  too 
sanguine,  but  temporize,  as  it  may  extend  a  week  or  so 
longer  than  you  expect,  and  so,  give  no  definite  progno- 
bIs  as  to  time.  '  -...;; 


64  VETERINARY   OPHTHALMOLOGY. 

^  Sulph.  Ziiic.  grs.  ij  to  the  oz.  of  distilled  water; 

IJ  Boric,  ac,  4  % 
Sig.  Gtt.  j  t.  i.  d.,  or  oftener;or, 

^  Ac.  Boric,  gr.  xi]. 

Aq.  Camph. 

Ag.  destill.  aa  3  ij. 
M.  Sig.  Gtt.  i.  t.  i.  d.  or  oftener. 

Purulent  Conjunctivitis,  Blennorrhoea,  Contagious 
Ophthalmia. — This  is  like  the  catarrhal,  but  with  in- 
tensification of  all  the  symptoms.  Due  to  the  same 
causes.  It  often  appears  as  an  epidemic,  where  num- 
bers are  crowded  together  with  poor  hygiene.  Is 
met  with  in  the  Asiatic  countries  especially.  The  dis- 
charges are  thick,  purulent  and  very  contagious.  Very 
great  danger  of  invasion  of  the  cornea,  which  results 
in  ulceration,  sloughing  and  probable  loss  of  the  eye, 
within  a  short  time. 

Treatment.  —  Mild  cases  should  receive  same 
treatment  as  the  catarrhal  form.  Severe  cases  re- 
quire isolation,  darkness  and  quiet ;  and,  first,  last 
and  all  the  time,  watch  the  pus,  which  77iust  7iot  be 
allowed  to  accumulate.  Sometimes  cleansing  is 
needed  every  few  minutes.  Application  of  cold, 
l)leeding,  scarification  of  the  conjunctiva,  if  the  swell- 
ing be  pronounced  and  chemosis  be  present,  and,  if  the 
lids  press  greatly  upon  the  globe,  canthotomy.  When 
the  discharga  appears,  astringent- lotions  every  few 


VETERINARY   OPHTHALMOI.6GY.  5i 

hours  and  some  caustic  application,  such  as  lunar 
caustic,  to  inner  surface  of  lids,  twice  daily,  or  possi- 
bly once  will  sufiBce ;  cold  compresses,  continuous  or 
changed  for  warm  ones  if  you  like.  Atropine  if  the 
cornea  becomes  involved.  If  one  eye  only  be  affected, 
the  other  must  be  guarded.  May  be  sealed  hermetically. 
When  a  case  is  seen  at  the  very  outset,  thorough 
cleansing  and  a  caustic  application  to  the  lids  (pal- 
pebral conjunctiva)  seems  to  abort. 

Goncrrhoeal  Conjunctivitis. — Gonorrhoeal  ophthalmia. 
This  does  not  differ,  except  in  manner  of  origin,  from 
any  other  purulent  conjunctivitis,  and  of  course  in  the 
equine  race  the  groom  must  be  looked  to  for  an  ex- 
planation. It  is  an  extremehj  violent  purulent  inflam- 
mation, caused  by  inoculation  from  the  urethral  dis- 
charge. It  may  destroy  the  eye  in  a  few  hours.  Still 
another  form  of  inflammation,  in  the  newly-born, 
called 

Ophthalmia  Neonatorum. — This  form  is  a  catar- 
rhal or  purulent  conjunctivitis,  usually  appearing 
shortly  after  birth  and  caused  by  contact  Avith  the 
vaghial  discharges  of  the  mother.  May  also  occur 
from  other  causes,  such  as  exposure  and  filth,  and  not 
appear  until  several  weeks  after  birth.  Assumes  all 
grades  of  severity. 

Tkeatmext.— Same  as  in  similar  conditions  in  the 
adult,  and  should  l)e  reguhrted  by  the  severity  of  the 
attack.      It  is  believed  by   many   that   caustics   are 


66  VETERINARY   OPHTHALMOLOGY. 

needless  in  the  very  young.  Even  claim  they  ara 
injurious,  and  that  a  mild  astringent  application  is 
all  that  is  necessary.  In  practice  among  physicians 
the  method  of  Crede  is  largely  employed,  which  con- 
sists in  dropping  into  the  eye  of  a  newly-born  one  drop 
of  a  2/0  solution  of  Arg.  nit. ;  and  it  seems  to  me  if 
there  is  any  apprehension  the  same  could  be  done  by 
the  veterinarian. 

Diphtheretis  Conjunctivitis  is  peculiar  in  that  it  may 
result  from  the  same  cause  as  the  other  forms.  This 
begins  with  great  heat, -redness,  swelling  and  tenderness 
of  the  lids,  with  rigidity  from  fibiinous  hifiltration.. 
Have  firm  swelling  of  conjunctiva  from  the  same 
cause,  and  a  pale,  smooth,  glistening  appearance  of  its 
surface.  Sometimes  have  a  grayish  exudation  mem- 
brane on  the  conjunctiva,  wliich  may  he  stripped  off. 
Discharge  of  flakes  of  lymph.  Advanced  stage  is 
marked  by  softening  of  the  parts  and  from  the  disap-, 
pearance  of  fibrinous  matter  and  by  discharge  of  pus. 
Great  tendency  to  shrinking  and  formation  of  cica- 
trices of  conjunctiva  in  healing.  The  cornea  is  apt  to 
suffer,  and  constitutional  disturbance  is  often  marked.. 
This  form  is  very  destructive,  and,  fortunately,  is  rare 
in  this  country  and  England. 

Treatment  not  very  effectual.  In  the  first  stage  ice 
compresses,  local  bleeding,  etc.;  astringents  and  caustics 
in  the  purulent  stage.  Atropine  should  be  used, 
throughout. 


VETERINARY   OPHTHALMOLOGY.  57 

Take  a,  case,  for  example  :  Diagnosis  has  been  satis- 
factorily made.  The  eye  is  cleansed  thoroufjhly.  If 
much  pain  and  restlessness  present,  instill  a  drop  of 
cocaine  4%  three  times,  at  five-minute  intervals.  If 
the  case  has  been  brought  you  while  young  {%.  e,,  the 
case,  not  the  patient),  evert  the  lid  and  paint  the 
palpebral  conjunctiva  with  a  strength  suitable  to 
the  severity  of  the  presenting  symptoms,  of  nitrate 
of  silver  solution,  even  using  the  stick  form  in 
aggravated  cases,  neutralizing  it  vntli  a  saturated  solu- 
tion of  Sod.  CIdoride,  before  the  lid  returns  to  its 
normal  position.  Then  commence  cold  applications, 
which  may  be  in  the  form  of  cracked  ice,  or  pieces  of 
clean  cloth  which  have  been  laid  on  ice.  Atropine,  one 
to  one  hundred  and  twenty  (1-120)  p.  r.  n.,  i.  e.,  from 
every  thirty  minutes  to  once  daily.  Also,  employ  any 
of  the  collyria  mentioned  through  the  lectures  you 
may  see  indications  for.  As  a  result  of  one  of  the  pre- 
viously desci'ibed  inflammations,  we  may  have  : — 

Granular  Lids  {Granular  conjunctivitis,  Granular 
ophthalmia.  Trachoma). — Generally  the  result  of  one  of 
the  previously  described  inflammations,  and  is  especi- 
ally a  chronic  condition,  although  sometimes  associated 
with  acute  symptoms.  The  palpebral  conjunctiva  pre- 
sents almost  exclusively  the  granulations,  of  which  we 
have  chiefly  two  kinds,  to  wit.,  enlarged  conjunctival 
papillae  and  the  frog-spawn  granulations.  These 
latter  are  grayish  bodies  resembling  sago  grains, '  and 


68  VETEKINAKY   OPHTHALMOLOGY. 

are  composed  of  lymphoid  cells  and  connective  tissue. 
Both  varieties  may  be  seen  separately,  but  more  often 
combined. 

Symptoms  are  those  of  an  annoying  conjunctivitis, 
and  may  be  more  or  less  severe.  If  the  process  is 
not  checked  the  cornea  becomes  ulcerated  and  vas- 
cular from  the  constant  irritation  from  friction  of 
the  roughened  lids  upon  it.  The  conjunctiva  and 
tissue  of  the  lids  may  become  atrophied  and  cica- 
trical, leading  to  entropion,  symblepharon,  xerophthal- 
mia, etc.  This  disease  is  more  often  found  in  the 
poorly  nourished,  bad  hygiene,  etc.  Runs  an  exceed- 
ingly tedious  course. 

Treatment. — Locally,  astringents  and  caustics,  sul- 
phate of  copper  crystal  being  the  favorite  one,  nitrate 
of  silver,  alum,  and  many  more.  Applications  may 
lose  effect  through  toleration,  and  change  becomes 
necessary,  and  regular  treatment  for  a  long  period  will 
be  necessary  to  establish  cure.  Before  beginning  any 
astringent  treatment  of  a  trachoma,  it  may  be  necessary 
to  use  hot  water,  atropine,  cocaine,  until  the  great  irri- 
tation, photophobia,  etc.,  subside.  Then  may  begin  with 
a  mild  astringent,  alum,  spray  of  tannin  and  glycerine, 
XX.  grs.  to  the  oz.  or  the  like.  In  very  obstinate 
cases,  after  a  fair  trial  with  other  remedies,  jequirity 
bean  {ahri(s  precatorius\  used  as  follows,  as  prepared  by 
De  Wecker  of  Paris.  The  bean  is  to  be  powdered  and 
mascerated  for   three  hours,   in  water,   at  ordinary 


VETERINARY   OPHTHALMOLOGY. 


59 


temperature,  and  of  a  3%  concentration.  The  recent 
infusion  is  best,,  as  it  loses  power  with  age.  With  a 
camel's-hair  pencil,  it  is  applied  to  the  lids,  two  or  three 
times.  Reaction  should  be  present  within  twenty-four 
hours.    If  not,  repeat  application.    This  is  painful  in 


Figr.  30. 

action,  and  ice-water  bags,  etc.,  should  be  employed. 
The  inflammation  will  last  for  at  least  two  weeks. 
Keep  patient  in  dark  stall,  and  quiet.  As  soon  as  the 
inflammatory  membrane  has  appeared,  use  the  cold  ap- 
plication until  reaction  has  abated.    Treat  the  case  as 


60  VETERINARY   OPHTHALMOLOGY. 

one  of  acute  trachoma,  when  sulphate  of  copper  crys- 
tal may  be  used  until  the  cure  is  complete.  When  the 
granulations  are  large  and  numerous,  they  may  be 
torn  out  and  destroyed  by  forceps,  and  as  this  is  a  very 
delicate  operation  great  care  is  to  be  exercised.  The 
lid  being  everted,  the  granules  are  stripped  off.  As 
may  be  readily  appreciated,  the  reaction  is  superb,  and 
is  to  be  carefully  treated  with  ice,  antiseptics,  etc. 
To  do  this,  an  anaesthetic  should  be  used.  Now,  in 
simple  chronic  blennorrhoea,  or  chronic  conjunctivitis, 
do  not  use  the  above  infusion.  The  results  are  apt 
to  prove  disastrous. 

Phlyctenular  Conjunctivitis.  (Pimple,  Gr.)  —  This 
form  is  characterized  by  a  small  yellowish-red  eleva- 
tion, or  phlyctenule,  on  the  summit  of  which  a  serous 
vesicle  forms,  which  vesicle  bursts,  and  leaves  a  small 
ulcer.  One  or  several  of  these  bodies  may  be  pres- 
ent, and  are  generally  situated  near  the  margin  of  the 
cornea.  Duration  about  ten  days ;  but  there  always 
is  great  tendency  to  relapse.  The  injection  of  the  con- 
junctiva may  be  general  or  partial.  A  triangular  leash 
of  vessels  runs  up  to  each  phlyctenule,  with  its  base 
pointing  toward  the  retrotarsal  fold.  The  appearance 
of  the  phlyctenule  is  attended  by  pain,  which  is  burn- 
ing ;  photophobia  and  lachrymation.  Often  associated 
with  phlyctenular  keratitis. 

Treatment. — Particular  attention  is  to  be  paid  to  the 
general  condition.    Atropine  1  to  120.    In  some  cases, 


VETERINARY   OPHTHALMOLOGY.  61 

application  of  a  mild  irritant,  such  as  calomel  or  ox 
mercur}',  ung.,  etc. 

Xow  for  a  word  on  dkir/nosis  of  a  differential 
character.  In  catarrhal  conjunctivitis,  the  injection 
is  general  over  the  conjunctiva,  and  on  pressure, 
through  tlie  lower  lid,  the  injected  vessels  are  seen  to 
move  over  the  sclerotic  with  the  membrane,,  (i.  e., 
the  conjunctiva).  There  is  tdtcays  redness  of  the 
fornix  conjunctiva,  and  usually  of  the  palpebral  ditto. 
There  is  a  muco-purulent  discharge,  more  or  less 
profuse,  dependent  on  degree.  The  iris  is  clear  and 
bright,  the  pupil  reacting  readily  to  light,  and  the 
cornea  is  clear  and  transparent.  In  Iritis,  the  injec- 
tion is  deep-seated,  surrounding  the  cornea  as  a  rosy 
zone.  This  is  not  accompanied  by  redness  of  the 
fornix,  or  palpebral  conjunctiva.  The  injected  ves- 
sels are  beneath  the  conjunctiva,  and  do  not  move 
with  it.  The  iris  is  discolored,  the  pupil  sluggish 
and  inactive,  and  vision  is  impaired.  There  is  usually 
very  severe  pain  in  the  eye  and  head,  generally  worse 
at  night.  In  Trachoma,  the  upper  lid,  and  particu- 
larly the  free  border  of  the  tarsus,  is  affected; 
the  granule  is  oval,  grayish-red,  and  opaque.  It  is 
imbedded  in  the  membrane,  and  is  less  prominent  than 
the  follicles.  They  may  be  found  on  the  ocular  con- 
junctiva, and  even  the  cornea.  In  the  granular  variety, 
the  affection  usually  takes  on  the  mixed  form,  present- 
ing follicular  and  papillary  hypertrophy  in  addition  to 


62 


VETEEINAEY   OPHTHALMOLOGY. 


the  new  growth.  There  is  also  general  lymphoid  infil- 
tration of  the  conjunctiva  and  of  the  deeper  tissues  of 
the  lid,  including  the  tarsus,  also  great  proliferation 
of  epithelia  and  formation  of  new  vessels.  In  papil- 
lary  trachoma,  the  location  is  predominately  over  the 
surface  of  the  tarsus,  instead  of  its  borders.  The 
enlarged  papillae  are  bright-red,  or  sometimes  red 
with  a  bluish  cast.  Follicular  Conjunctimtis  espe- 
cially affects  the  lower  lid,  and  particularly  the  cul- 
de-sac.  The  follicle  is  round,  or  elongated,  pale  and 
semi-transparent.  Is  more  prominent  and  sharply 
raised  above  the  surface  of  the  conjunctiva,  and  can 
be  removed  or  separated  from  it.  Its  general  arrange- 
ment is  in  rows  parallel  to  the  free  margin  of  the  lids. 
Pterygium   (a  little   wing,  Gr.).  —  Quite  a  common 

affection,  result  of  in- 
flammation and  from 
constant  exposure. 
Consists  of  hypertro- 
phy   of    conjunctiva, 
and   sub-conjunctival 
tissue.     In  form  it  is 
a  triangular  vascular 
prominence,   general- 
ly at  the  nasal  side  of 
the  eye,  with  the  base  toward  the  inner  canthus  and  its 
rounded  apex  at  the  edge  of  the  cornea,  or  encroaching 
more  or  less  viyon  the  cornea.    We  notice  two  forms> 


F.g.  31 


YETERIXAEY   OPHTHALMOLOGY.  63 

or  one  form  of  different  degree — i.  e.,  a  thin  (tenne), 
and  a  thick  {a-assum).  Requires  no  treatment  unless 
it  extends  upon  the  cornea  so  as  to  obstruct  vision. 
May  then  be  removed  by  (1)  excision,  which  is  dis- 
secting the  growth  off  of  the  cornea  and  sclerotic,  to  a 
point  near  the  canthus,  and  uniting  the  conjunctival 
wound  by  sutures;  (2)  tmnsj^lantation,  which  is  per- 
formed by  dissecting  it  off  up  to  the  base  and  then  insert- 
ing it  into  an  incision  made  in  the  conjunctiva,  parallel  to 
the  lower  edge  of  the  cornea  and  retaining  it  there  by 
sutures;  or  (3)  ligature  thread  passed  around  the 
growth  at  two  or  more  points,  so  as  to  cause  stran- 
gulation. 

As  the  result  of  severe  chronic  conjunctivitis  we 
meet  with  Jurojyhthalmia.  Dryness  of  the  eye.  This 
is  an  atrophied  condition,  and  of  cicatrical  change 
in  the  cornea,  conjunctiva  and  sub-conjunctival  tissues. 
The  surface  is  of  a  dirty  greenish  or  grayish  color,  or 
tendinous  appearance.  Also  is  dry,  scaly,  and  stiff 
from  destruction  of  secretory  apparatus.  Obliteration 
of  the  palpebral  folds,  and  more  or  less  adhesion  of 
lid  to  globe. 

TREATiiEXT  is  inefficient.  The  dryness  may  be  alle- 
viated by  bland  applications,  such  as  milk,  glycerine, 
vaseline,  etc. 

Tumors  of  the  Conjunctiva. — Pinguecula',  a  small 
yellowish  tumor,  fatty  in  appearance,  situated  near 
the  corneal  margin,  and  chiefly  seen  in  the  aged ;  con- 


64  VETERINARY   OPHTHALMOLOGY. 

sists  of  hypertrophied  conjunctiva  and  epithelium ; 
they  are  harmless  and  need  no  treatment.  Dermoid 
tumors,  smooth  and  yellowish,  covered  with  con- 
junctiva and  perhaps  with  short  hairs ;  composed  of 
connective  tissue  and  fat ;  generally  congenital.  Ex- 
cise them.  Warts,  similar  to  those  on  prepuce,  may 
occur  on  any  part  of  the  conjunctiva ;  snip  off  with 
scissors. 

Cancer  should  be  treated  as  elsewhere. 


CHAPTER  Vn. 
THE  CORXEA. 

Cornea  is  elliptical  in  shape,  is  perfectly  trans- 
parent, which  is  clue  to  the  arrangement  as  well  as  the 
transparency  of  its  individual  parts.  It  closes  the 
anterior  opening  of  the  sclerotic  and  forms  one-fifth  of 
the  external  envelope  which  it  completes.  It  fits  into 
the  sclerotic  like  the  crystal  of  a  watch  into  its  case, 
the  cornea  being  beveled  on  its  outer  edge.  The 
cornea  is  composed  offivelayers:  (1)  The  anterior  epithe- 
lial layer  is,  as  its  name  indicates,  composed  of  epithelia 
disposed  in  layers  and  continuous  with  that  of  the 
conjunctiva.  (2)  Boicman^s  membrane.  A  very  elastic 
tissue  which  possesses  a  tendency  to  curl  up.  Neither 
acids  or  boiling  renders  this  layer  opaque  as  it  does 
the  other  layers.  This  layer  has  no  lacunae  nor  lymph 
canals,  but  contains  fibrillse  and  faciculi.  Has  no 
fixed  cells  or  movable  corpuscles.  Is  intimately  ad- 
herent to  the  parenchyma.  Cannot  be  separated  as  a 
distinct  layer.  (3)  The  parenchyma  is  composed  of  fine 
fibrillae  united  into  fasciculi,  bound  together  by  a 
cement  matter.    Has  a  system  of  canals  which  are  a 

continuation  of  lymphatic  spaces.    These  lymphatic 
5  65 


66 


VETERINAKY  OPHTHALMOLOGY. 


canals  contain  cells.  The  fasciculi  are  in  layers,  one 
above  the  other.  The  canals  in  the  cornea  are 
hollowed  out  of  the  tissue  formed  by  the  cement  and 
fasciculi,  and  may  be  resolved  into  shallow  spaces,  very 
numerous  and  communicating  with  each  other  by 
canaliculi,  which  vary  in  size  and  form  a  net-work 
throughout  the  parenchyma,  penetrating  between  the 
fibers  and  ramifying  from  layer  to  layer.  Their  func- 
tion is  to  convey  the  nourishing  lymph.    Three  varieties. 


•^^ 


of  cells  may  be  found  in  these  canaliculi,  fixed,  wander- 
ing and  pigment.  The  fixed  lie  in  the  lacunae,  and 
send  prolongations  out  into  the  canals.  The  vmnder- 
ing  are  brighter,  larger,  and,  as  the  name  implies,  have 
power  of  motion.  The  pigment  is  found  only  at  the 
periphery  of  the  cornea.  On  the  inner  side  of  the  tissue 
proper  of  the  cornea  is  a  lining  membrane  called  (4) 
Mescemef  s.    It  is  firm,  elastic,  glossy  in  appearance  and 


VETERINARY   OPHTHALMOLOGY.  67 

highly  refractive.  Then  the  (5)  endothelial  layer,  com- 
posed of  a  single  layer  of  cells.  This  layer  is  reflected, 
on  the  anterior  surface  of  the  Iris.  In  or  on  the  cornea 
<tre  no  blood  vessels.  The  anterior  ciliary  arteiies 
furnish  branches,  which  approach  the  limbus,  forming 
loops.  Blood  vessels  on  the  cornea  are  indicative  of 
either  a  pathological  condition  or  an  attempt  of 
nature  to  repair.  The  nerves  come  from  the  ciliarj'-, 
which  pass  the  ciliary  body  and  form  a  plexus  around 
the  border  of  the  cornea.  Their  terminal  fibrillse  are 
most  abundant  in  the  epithelium  and  anterior  layers 
of  the  cornea.  Some  few  twigs  come  from  the  con- 
junctival nerves. 

Injuries  and  Wounds.— Many  varieties — clean  cut, 
-contused,  scraped,  etc.  Clean  cut,  if  not  too  large, 
usually  heal  and  leave  no  trace.  Contused  wounds 
are  apt  to  cause  suppuration. 

The  great  danger  is  of  injury  to  the  lens,  which 
would  be  apt  to  result  in  cataract,  or  to  the  iris,  which 
may  prolapse,  or,  becoming  adhered  to  the  corneal 
puncture,  cause  staphyloma. 

Treatment — The  primary  treatment  is  to  place  the 
eye  in  a  state  of  rest  and  allay  irritation  by  soothing 
applications.  Atropine  and  cocaine  should  be  applied 
several  times  daily ;  atropine  1  to  120,  or  stronger  if 
need  be ;  cocaine  4%.  Cold  compresses  if  seen  early 
enough.  If  the  epithelium  is  abraded  a  few  drops  of 
olive  oil  allays  irritation.    The  compress  bandage  re- 


68  VETERINARY   OPHTHALMOLOGY. 

strains  motion  and  so  is  useful;  also  excludes  lights 
If  the  corneal  wound  be  central,  use  atroioine,  and 
quick.    If  peripheral,  eserine  %%. 

Foreign  bodies  are  of  frequent  occurrence,  the 
most  common  being  dust,  glass,  metal,  etc.,  and  they 
cause  severe  reaction  according  to  the  depth  to  which 
they  penetrate  and  length  of  time  they  remain.  Ex- 
ceptionally, the  reverse  may  be  the  case.  They  are 
seen  easily,  generally,  and  oblique  illumination  will 
facilitate  a  search.  If  superficial,  remove  with  a  spud. 
If  firmly  imbedded,  use  forceps  or  a  needle.  To  avoid 
a  deeply  seated  particle  falling  bacl-irards  into  the 
anterior  chamber  during  attempts  at  removal,  a  broad 
needle  may  be  passed  into  the  anterior  chamber  so  as 
to  form  a  base  on  which  to  work.  Cocaine  4%  must 
be  used,  and  an  eye-speculum  will  insure  better  results 
if  used. 

Burns,  injurie3,  from  chemical  agents,  etc.,  are  apt  to 
cause  sloughing  and  permanent  opacities.  Use  oil, 
cocaine ;  wash  the  eye  thoroughly,  and  neutralize  acids 
by  alkalis — for  instance,  soda,  dram  to  the  ounce. 
Should  the  offending  matter  be  lime,  use  vinegar  and 
water,  oil,  and,  above  all,  don't  put  a  little  water  into 
the  eye. 

Abrasions  of  epithelium  appear  as  a  roughened,  glist- 
ening facet,  and  are  very  painful.     Use  oil  collyria. 

Keratitis  (inflammation  of  the  cornea.)  Result  of  in- 
juriss,  exposure,  constitutional  diseases,  mal-nutrition> 


VETERINARY   OPHTHALMOLOGY.  69 

inflammation  of  adjacent  parts,  etc. ;  is  one  of  the  most 
frequent  diseases  of  the  eye.  It  leads  to  vascularization, 
cell  proliferation  and  suppuration,  each  of  these  con- 
ditions being  more  or  less  prominent  according  to  the 
kind  of  inflammation  present.  Attending  these  con- 
ditions we  find  the  vision  is  impaired,  ciliary  irritation, 
which  is  aliomjs  ominous  (a  zone  of  fine  vessels  appearing 
around  the  corneal  margin),  pain,  photophobia,  lachry-. 
mation,  conjunctival  congestion  and  contraction  of  the 
pupil.  The  cornea  will  be  turbid  and  swollen.  If 
ulcerated,  it  becomes  thinned,  and  perhaps  rupturing 
permits  deeper  parts  to  become  prolapsed  or  escape. 
If  thinned  or  softened  it  may  bulge  forward  from 
intra-ocular  pressure,  forming  staphyloma.  After 
recovery,  indelible  opacities 
and  alterations  of  curvature 
may  remain,  with  correspond- 
ing loss  of  vision.  In  treating 
acute  corneal  inflammations  it 
Is  the  cardinal  rule  to  avoid 
all  irritants  and  caustics  and 
to  pay  special  attention  to 
hygiene  and  general   health.  ^" 

Atropine,  darkness,  and  rest  of  the  eye  are  always 
proper.  Cold  and  local  bleeding  may  be  tried  if  symp- 
toms are  very  acute.  When  the  disease  does  not 
improve  under  this  treatment,  or  becomes  chronic,  the 
proper  treatment  requires  special  experience.     Where 


70 


VETEKINAEY   OPHTHALMOLOGY. 


there  is  great  photophobia,  or  spasm  of  the  orbicularis^ 
the  cold  douche,  forcible  stretching  apart  of  the  lids, 
canthoplasty,  insufflations  of  calomel,  ointments 
of  mercury,  etc.,  are  employed. 

Keratitis  Vasculosa. — This  is  characterized  by  a 
grayish  cloudiness  of  the  cornea  with  network  of 
vessels  in  the  affected  region.  The  epithelium  may  be 
shed,  causing  great  pain  from  the  exposure  of  nerves. 
Under  favorable  circumstances,  tends  to  recovery. 
May,  however,  run  on  into  other  forms  and  be  combined 
with  them. 


Fig.  34. 


Phlyctenular  Keratitis  is  characterized  by  phlyc- 
tenules in  the  superficial  layers  of  the  cornea  like  those 
in  phlyctenular  conjunctivitis.  These  phlyctenules 
appear  as  inflammatory  nodules,  singly  or  in  groups, 
on  any  part  of  the  cornea,  but  most  often  at  the  margin. 
May  be  surrounded  by  vesicles,  which  vesicles  may 


VETERINARY    OPHTHALMOLOGY.  71 

burst  and  leave  a  ring  ot  ulcers.  A  triangular  net- 
work of  vessels  will  be  seen  running  toward  phl^^c- 
tenule,  its  base  towards  the  retrotarsal  fold  and  its 
apex  at  the  phlyctenule,  if  this  is  at  the  edge  of  the 
cornea.  If,  however,  the  phlyctenule  lies  some  distance 
from  the  corneal  border,  the  apex  of  the  triangle 
appears  cut  off  at  the  edge  of  the  cornea,  thus  leaving 
a  space  of  clear  tissue  intervening  between  it  and  the 
phlyctenule.  If  the  attack  is  severe,  vascular  keratitis 
may  supervene,  vessels  then  would  extend  upon  the 
cornea  quite  up  to  the  phlyctenule.  The  secretions 
from  the  eye  irritate  and  excoriate  the  parts  over  which 
they  flow. 

Interstitial  Keratitis. — Also  termed  Parenchymatoxis 
and  Difficse.  Will  have  swelling  and  diffuse  cloudi- 
ness, which  cloudiness  usually  extends  from  margin 
to  center,  and  very  rarely  the  reverse.  May  be  very 
sliglit,  and  again  may  be  very  dense,  simulating  ground 
glass.  May  be  irregular  in  density,  causing  white  and 
grayish  patches.  The  corneal  surface  usually  loses  its 
polish  and  assumes  a  dull  stippled  appearance,  due  to 
loss  of  epithelium.  Vessels  may  appear  in  the  corneal 
substance,  running  from  margin  toward  center,  and  are 
sometimes  numerous  enough  to  cause  a  bright  red  re- 
ilex.  Happily,  there  is  very  little  tendency  toward 
ulceration.  This  form  is  tedious,  taking  months  to 
cure. 

Suppurative    Keratitis. — The   inflammatory  infiltra- 


72 


VETERINAKY   OPHTHALMOLOGY. 


Abscess. 


Onyx. 


Hypopyon^ 
Onyx. 


..  Onyx. 


tion  becomes  changed  to  pus, 
which  pus  shows  as  a  yellow 
opacity  in  the  corneal  tissues. 
The  suppuration  may  be  limit- 
ed, or  the  entire  cornea  may  be 
involved.  If  inclosed  by  corneal 
tissue,  forms  an  abscess ;  if 
superficial,  an  ulcer.  Some- 
times the  pus  sinks  down  be- 
tween the  layers,  forming  an 
onyx  from  its  resemblance  to 
the  lunula  of  the  finger-nail. 
Often  will  see  hypopyon  in  the 
{interior  chamber,  caused  by 
the  pus  settling  to  its  bottom. 
These  two  conditions  may  co- 
exist. Vascularity  may  attend  the  suppuration,  and 
with  acute  symptoms,  or  there  may  be  very  little  pain 
and  vascularity,  which  latter  form  is  very  dangerous 
from  death  of  tissue  and  sloughing.  Abscesses  may  be 
absorbed  or  burst  open,  or  pus  may  undergo  fatty  or 
chalky  degeneration,  leaving  dense  opacities.  An  ulcer 
may  be  an  opened  abscess.  But,  remember,  superficial 
ulcers  may  occur  without  a  primary  abscess.  Ulcers 
are  of  variable  size,  shape  and  depth,  and  are  dangerous 
according  to  their  location.  The  crescentic  marginal 
is  exceedingly  dangerous  from  its  tendency  to  encircle 
the  cornea  and  thus  deprive  the  central  cornea  of  nutri- 


Fig.  35. 


YETEEIlsrARY   OPHTHALMOLOGY.  73 

tion.  If  an  ulcer  extend  deep  enough  to  reach  the 
membrane  of  Descemet,  it  may  bulge  forward  through 
the  ulcer  like  a  vesicle,  and  thus  form  a  hernia  of  the 
cornea  or  heratocele^  and  is  usually  followed  by  per- 
foration. Larger  ulcers  generally  lead  to  staphyloma. 
When  perforation  does  occur,  there  is  escape  of  the 
aqueous  and  a  carrying  forward  of  the  iris  and  lens. 
If  the  iris  becomes  fast  into  the  Avound,  it  forms  an 
anterior  synechia.  If  perforation  is  lai'ge  enough,  the 
iris  may  ijrotrxide^  becoming  adherent  around  the 
edges,  leaving  synechia.  Sometimes,  after  healing  of 
the  ulcer,  there  will  be  re-accumulation  of  aqueous  and 
tearing  loose  of  the  adhesions  through  the  action  of 
the  pupillary  muscles,  the  iris  then  assuming  its  free- 
dom, floating  in  the  aqueous.  As  before  mentioned, 
the  lens  may  also  be  carried  forward  against  the  per- 
foration, and  if  it  return  to  its  position  we  may  see 
some  matter  deposited  on  its  anterior  capsule,  thus 
constituting  anterior  capsular  cataract.  Remember 
that  adhesions  sometimes  formed  may  never  be  broken, 
and  the  anterior  chamber  may  be  never  re-established. 
If  the  aperture,  resulting  from  ulcer  and  sloughing, 
be  extensive  enough  to  allow  of  escape  of  all  the 
contents  of  the  eye,  atrophy  of  the  globe  will  result. 
The  rule  in  healing  of  ulcers  is  that  some  trace 
be  left,  from  a  slight  cloud  to  a  dense  opacity,  and 
are  variously  termed,  according  to  degree — nubecula^ 
a    mist ;    nebula^   a    cloud ;    macula^   a    spot.      And 


74  VETERINARY   OPHTHALMOLOGY. 

often  a  cloudiness  which  will  be  prominent  during' 
convalescence  will  clear  up  to  a  very  satisfactory  de- 
gree.  But  the  reverse  may  obtain.  During  the  heal- 
ing process  vessels  may  be  seen  traversing  the  cornea, 
but  this  is  physiological  and  necessary  to  absorption. 
Suppurative  inflammation  may  result  from  many  and 
identical  causes  with  other  forms,  and  is  the  dread  of 
operators.  Bruised  and  lacerated  wounds  are  also  apt 
to  give  rise  to  suppuration.  Cases  of  severe  conjunc- 
tivitis sometimes  result  so. 

Treatment  includes  the  ordinary  remedies  for  kera- 
titis, remembering  to  avoid  all  irritants.  Even  large 
hypopyon  are  absorbed,  and  it  is  very  seldom  necessary 
to  evacuate.  Paracentesis  may  be  frequently  repeated 
in  cases  of  increased  tension.  Hot  fomentations  are 
often  useful,  especially  in  asthenic  cases,  where  there 
is  danger  of  death  of  tissue.  In  deej)  ulcers  it  is  better 
to  perform  paracentesis  through  their  base  than  to 
permit  spontaneous  perforation.  In  ulcers  that  are 
stqyerjicial  and  indolent,  Scemisches  operation  is  indi- 
cated and  performed  as  follows : 

Introduce  (after  cocaine)  a  spring  speculum  ;  grasp 
the  conjunctiva  opposite  point  of  counter  puncture 
with  fixation  forceps,  (fig.  37)  enter  the  cornea  at  right 
angles  with  a  Graefe's  knife  (fig.  38)  thus  dividing  the 
minimum  amount  of  tissue ;  then  turn  the  knife  in- 
ward,  avoiding  the  iris  and  lens.  Make  this  primary 
incision  inside  the  ciliary  region,  on  account  of  risk 


VETEKINAFvY   OPHTHALMOLOGY. 


75 


of  sympathetic  ophthal- 
mia. 

This  primary  incision 
should  be  about  two 
ram.  from  the  edge  of 
the  ulcer  and  brought 
out  about  the  same  dis- 
tance on  the  other  side. 
The  knife  then  cuts  its 
way  out  through  the 
bottom  of  the  ulcer. 
The  incision  may  be 
kept  open  by  passing 
a  fine  probe  through  it  daily,  using  extreme  ascepsis 
and  antisepsis,  and  the  tension  kept  down  until  repair 
begins.  Corneal  abscess  may  be  treated  in  a  similar 
manner.     You  remember  my  speaking  of  paracentesis 


Fig.  36. 


Fig.  37 


of  the  cornea, — it  is  performed  as  follows  :  Introdce  a 
needle  or  blade  of  an  iridectomy  knife  through  the 
cornea  near  its  margin  and  allow  the  aqueous  to  draia 


=-e 


G  TiPMAMN  Jt  CO 


Fgi. 


76  VETERINAKY   OPHTHALMOLOGY. 

off  sloidy  alongside  the  instrument.  The  one  care  in 
this  is  to  avoid  too  sudden  an  escape  of  the  fluid  and 
possible  prolapse  of  the  iris.  Again,  a  too  sudden 
diminution  of  intra-ocular  tension  is  apt  to  result  in 
shock. 

Pannus. — A  vascular  opacity  of  the  cornea,  non-in- 
flammatory. A  new  growth — neoplasm — the  result  of 
a  preceding  inflammation.  The  term  is  applied  also  to 
acute  and  chronic  vascular  keratitis  where  the  forma- 
tion of  new  tissue  is  still  in  progress.  A  part  or  the 
entire  cornea  may  be  involved.  Two  forms,  remember, 
I  spoke  of — tenue,  thin,  and  crassum,  thick  (or beefy). 

In  extreme  degrees  the  cornea  may  appear  de- 
cidedly red  and  fleshy,  and  this  condition  may  continue 
for  months  and  years  with  no  change.  The  rarity  is 
complete  cure,  for  usually  a  good  cure  leaves  opacities 
of  different  degrees.  The  cornea  may  become  thin  and 
bulge  forward.  Trachoma  is  the  cause  of  the  majority 
of  cases  of  pannus,  and  these  cases  may  present  corneal 
granulations  similar  to  those  upon  the  lids.  It  may 
be  traumatic  from  long  continued  irritation,  such  as 
that  from  foreign  particles,  inverted  cilia,  etc. 

Treatment. — After  removing  the  cause,  hasten  reso- 
lution of  the  opacity,  and  to  this  end,  if  no  inflamma- 
tion be  present,  irritating  powders  and  unguents  are 
used.  Sometimes  a  too  constant  application  of  a  remedy 
wears  it  out  and  a  cliange  becomes  necessary.  If  the 
entire  cornea  be  involved,  the  pannus  in  a  high  state 


VETERINAKY   OPHTHALMOLOGY. 


IT 


of  vascularity,  and  no  ulcers  existitiff,  the  Jequirity 
infusion  offers  good  results.  Opacities  are  frequently 
the  result  of  corneal  inflammations  and  cicatricial 
deposits.  While  they  are  classified  according  to  de- 
gree, they  are  practically  divided  into  superficial  and 
deep,  the  former  affecting  the  epithelial  layer,  the 
latter  the  parenchyma.    A  faint  superficial  opacity  is 


Kg.  89. 


Fig.  4a 


called  nebula  (L.  fog),  a  thick  dense  one  leucoma 
(Gr.  white).  A  cicatrix  combined  with  prolapse  and 
adhesion  of  the  iris  is  called  leucoma  adherans.  May 
see  white,  chalky  deposits,  which  may  be  the  result  of 
an  application  of  lead  lotion  where  ulceration  was  pre- 
sent in  the  corneal  tissues.  Many  opacities  disappear 
spontaneously  in  the  young  and  robust.  As  a  rule  the 
more  recent  and  superficial  the  opacity  the  better  the 


78  VETERINARY   OPHTHALMOLOGY. 

chance  for  removal.  The  application  of ^/leZy  powdered 
calomel  will  assist  absorption  by  exciting  hypersemia 
and  increased  tissue  change.  Deposits  of  lead  may  in 
some  cases  be  scraped  away,  and  the  ulcer  which 
results  may  be  filled  up  with  transparent  tissue. 

Cicatricial  Staphyloma  is  generally  the  result  of 
ulceration,  for  the  floor  of  an  ulcer,  being  very  thin,  is 
therefore  very  apt  to  yield  to  the  intra-ocular  pressure 
and  bulge. 

In  the  process  of  healing  the  bulged  portion  is  apt 
to  be  covered  with  cicatricial  tissue,  and  a  staphyloma 
is  left,  bluish-white  in  appearance.  Remember  the 
leucoma  adherans,  which  may  be  a  complication. 

Kerato-conxis. — Conical  cornea  is  a  cornea  cone- 
shaped.  It  is  a  protrusion  of  the  cornea,  and  its  cause 
is  not  very  well  understood.  Usually  congenital,  but 
vway  appear  after  inflammations. 

Fistula  of  the  cornea  may  be  the  result  of  a  perfora- 
tion, ulcer  or  wound.  Difficult  of  cure,  indeed.  Contin- 
ual irritation  from  the  constant  dribbling  of  aqueous. 
Pacqnelin's  cautery,  carefully  cauterizing  the  edges  of 
the  fistula,  or  a  delicate  probe  dipped  in  carbolic  acid 
and  lightly  touched  to  the  opening.  Atropine,  etc. 
A  compress  bandage,  enjoining  rest,  from  quiet  and 
gentle  pressure. 


CHAPTER  VIII. 
THE  SCLERA. 

The  Sclera  is  a  tough,  dense,  fibrous  structure,  con- 
tinuous with  the  cornea.  Is  a  little  elastic.  Possesses 
blood  vessels,  in  which  it  differs  from  the  cornea.  Its 
fibrillse  are  gathered  into  bundles  and  cross  each  other 
indiscriminately.  Lymph  canals  ramify  through  these. 
The  cells  are  fixed,  wandering  and  pigment.  Loose 
connective  tissue  covers  the  sclera  in  front,  and  is 
called  episcleral,  and  this  in  turn  is  covered  by  the 
conjunctiva.  The  sclera  is  pierced  at  the  inner  side  of 
the  axis  by  the  optic  nerve.  This  entrance  is  also 
heloxo  the  exact  center.  This  place  of  entrance  is  sieve- 
like and  is  called  the  Icnnina  cribrosa,  in  the  center  of 
which  is  a  larger  opening,  the  porus  ojyticus,  through 
which  passes  the  arteria  centralis.  Surrounding  the 
optic  nerve  the  sclera  is  perforated  by  vessels  and 
nerves  called  posterior  or  short  ciliary,  which  go  to 
the  choroid,  ciliary  body  and  iris.  In  front  it  is  pierced 
by  the  anterior  ciliary  vessels.  In  front  the  sclera 
presents  an  elliptical  opening,  whose  greatest  diameter 
is  transverse  and  whose  border  is  bevelled  on  the  inner 
side  (remember  the  bevelling  of  the  cornea),  and  fits 


80  VETERINAEY   OPHTHALMOLOGY. 


Fig.  41. 


VETERINARY   OPHTHALMOLOGY.  81 

nicely  over  the  corneal  circumference.  The  sclera  is 
thickest  around  the  optic  nerve  entrance,  grows 
thinner  at  the  equatorial  region  and  thicker  again 
anteriorly.  The  existence  of  nerves  in  the  sclera  is 
denied  by  some. 

Episcleritus  appears  as  a  swelling  near  the  cornea, 
dusky  red  in  color  and  most  frequently  seen  over  the 
insertion  of  the  rectus  externus  muscle.  Gives  no 
evidence  of  tendency  to  ulceration  or  suppuration  and 
looks  like  a  phlyctenule.  Irritation  and  tenderness. 
Rebellious  to  treatment.  Met  with  in  those  of  rheu- 
matic tendencies  principally,  and  therefore  constitu- 
tional remedies  are  the  most  valuable,  (i.e.,  remedies 
for  rheumatism),  and,  locally,  atropine,  and  pilocarpin 
hypodermically  administered. 

Staphlyoma  of  the  Sclerotic. — Before  describing  this 
form  Avill  mention  AV/c/vV/.s-,  which  appears  as  a  general 
faint  pinkish  tinge,  due  to  injection  of  superficial  vessels 
of  the  sclera.  In  its  later  and  severer  stages  this  becomes 
more  bluish.  If  seen  early  it  is  hard  to  distinguish 
between  it,  iritis,  and  conjunctivitis,  but  the  aqueous 
is  clear  and  no  adhesions  are  present,  and  that  throws 
out  iritis  ;  and  having  no  secretion,  there  can  be  no 
conjunctivitis.  This  is  another  rheumatic  accompani- 
ment, and  De  Wecker  of  Paris  says  in  the  human  being 
it  accompanies  the  articular  rheumatism  by  preference. 
Now  this  inflammation  of  the  sclera,  from  \veakening 
€Uid  consequent  thinning,  may  lead  to  staphyloma,  and 


82 


VETERLNAEY   OPHTHALMOLOGY. 


Fig.  42. 
Anterior  portion  and  ciliary  region  of  the  eye.  C,  cornea  ;  c  S,  Schlemm's 
canal ;  O  s,  ora  serrata  ;  1  p,  pectinated  ligament ;  e  F,  Fontana's  space ; 
T,  tendinous  ring  ;  m,  meridional  fibers  r,  radiating  fibers  ;  ;  c,  circular 
fibers  of  the  ciliary  muscle  ;  Z,  zone  of  Zinn.  The  full  lines  indicate 
the  crystalline  lens,  iris,  and  ciliary  body  in  a  state  of  rest,  the  dotted. 
Jines  show  the  same  in  a  state  of  accommodation. 


YETERTNAEY   OPHTHALMOLOGY.  83 

«o  here  we  are.  It  may  be  complete  or  partial.  Again, 
it  maybe  anterior,  between  the  cornea  and  the  equator 
or  posterior,  around  the  optic  nerve.  Anterior  staphly- 
loma  has  a  dirty  bluish  color  from  the  choroid  shininfj 
through,  and  is  of  variable  size,  sometimes,  indeed,  in- 
volving tlie  whole  front  of  the  eye.  Where  the  tumor 
is  small,  paracentesis  with  pressure  may  check  further 
progress.  If  verj'-  extensive  it  may  be  necessary  to 
enucleate  the  eye.  When  the  bulging  extends  all 
around  the  sclera  is  called  annular  staphyloma^  and 
when  complete  may  protrude  so  far  as  to  be  called 
hvphthalmus. 

Injuries  of  the  Sclera. — ^Dangerous,  as  they  com- 
plicate adjoining  tissues  and  as  they  permit  contents 
of  tlie  eye  to  escape.  Small  wounds  may  heal 
re.adily.  Clearly  cut,  may  be  united  by  a  fine  suture  ; 
2C[v^ protrudiiuj  choroid  or  vitreous  must  he  cut  off  with 
scissors  first.  Patient  kept  quiet,  and  ice  compresses 
employed.  If  the  wound  is  extensive  and  in  the  ciliary 
region,  enucleate  and  thus  avoid  sympathetic  trouble. 


CHAPTER  IX. 

THE  IRIS. 

Iris. — The  Iris  forms  in  the  interior  of  the  eye,  in  front 
of  the  crystalline  lens,  a  veritable  diaphragm,  with  a  cen- 
tral opening — the  pupil.  Is  a  beautifully  colored  and 
contractile  membrane.  It  is  attached  at  its  periphery 
to  the  sclera  tlirough  the  fibers  of  the  li (j amentum lycc- 
tinatum.  The  shape  of  the  iris  is  elliptical.  It  rests 
(the  pupillary  margin)  posteriorly,  on  the  lens  cap- 
sule. Its  anterior  surface  is  free.  The  iris  is  con- 
tinuous with  the  ciliary  body  and  choroid,  and 
together  these  constitute  the  uveal  tract,  upon  which 
the  aqueous  humor,  the  lens  and  vitreous,  depend  for 
nourishment.  The  iris  divides  the  space  between 
the  cornea  and  the  anterior  face  of  the  lens  and 
internal  extremities  of  the  ciliary  processes  into  two 
compartments  of  unequal  size  —  the  anterior  being 
the  larger  and  the  posterior  having  only  a  virtual  ex- 
istence, as  the  iris  rests  upon  the  lens  capsule.  Both 
the  anterior  and  posterior  chambers  contain  the  aqueous, 
humor  in  which  the  iris  floats  free.  The  anterior 
surface  of  the  iris  is  lined  with  a  layer  of  epithelial  cells> 

which  are  continuous  with  those  on  the  posterior  sur- 

84 


VETERINARY   OPHTHALMOLOGY.  85 

face  of  the  cornea.  On  the  back  of  the  iris  is  a  thicker 
layer  containing  i:»igment,  wliich  is  continuous  with 
that  of  the  ciliary  body  and  choroid.  Xow,  this  layer 
of  pigment,  the  tcveciy  may  be  frequently  seen  as 
small  bodies  on  a  pedicle  or  stem  in  the  pupillary 
aperture.  Indeed,  they  may  pass  through  and  show 
in  the  anterior  chamber.  Called  soot-balls  (corpora 
nigra).   More  often  seen  at  the  upper  (pupillary)  border. 

In  color  they  are  brownish- 
black.  Unstriped  muscle  fiber 
is  the  predominating  constituent 
of  the  iris,  contained  in  a  stroma 
of  connective  tissue,  which  also 
contains  the  vessels,nerves,  lymph 
spaces  and  cells.  Around  the 
pupil  some  certain  fibers  are  ar-  ^     ^ 

ranged  circularly.     This  is   the 

sj^hincter  jmjnlhv,  and  the  dilator  ai  the  pupil  is  formed 
of  radiating  fibers.  The  peculiar  disposition  or  juncture 
of  these  two  sets  of  fibers  is  that  they  join  each 
other  near  the  pupil  in  curves,  as  I  here  depict. 
The  sphincter  governed  l)y  the  third  pair,  the  dilator 
by  the  sympathetic.  The  iris  has  three  dift'erent  classes 
of  nerves  sent  to  it  from  the  ciliary  ganglion,  which 
ganglion  has  three  roots — sensitive,  motor  and  sympa- 
thetic. The  twigs  which  emanate  from  this  ganglion 
pass  to  the  sclera,  surrounding  the  optic  nerve.  These 
are  named  the  short  ciliary.     The  two  long  posterior 


#0 


86 


VETERINARY   OPHTHALMOLOGT. 


ciliary  arteries  form  the  circulus  iridis  major  by  unit- 
ing with  the  branches  of  the  anterior  ciliary  arteries. 
From  these  we  have  branches  which  form  another 
ring,  the  circulus  iridis  minor,  formed  by  anasto- 
mosing. The  major  is  formed  at  the  ciliary  region. 
The  minor  gives  off  capillaries,  which  in  turn  become 
veins,  and,  the  circulation  being  established,  is  re- 
turned in  the  same  manner  as  above  described.    The 


Txissc^ 


^   C  I 

Fig.  44 

iris  regulates  the  amount  of  light  admitted  to  the 
eye's  interior,  and  by  excluding  peripheral  rays  ad- 
mits of  acute  vision. 

Iritis. —  Inflammation  of  the  iris  is  the  result  of  in- 
juries, cold,  rheumatics,  extension  of  inflammation  from 
other  parts,  etc.  Three  principal  divisions:  (1)  plastic, 
(2)  purulent,  and  (3)  serous,  but  a  description  of  one 


YETERIXARY   OPHTHALMOLOGY.  87 

general  case  will  suflBce 
for  the  general  practi- 
tioner. With  the  appear- 
ance  of  inflammation, 
and  its  symptoms,  will 
have  an  exudate  showing 
at  the  margin  of  the 
pupil.  This  may  go  on  to 
such  a  degree  that  the 
aqueous  shows  decided   '  ^'^-  ^^' 

turbidity,  iris  becomes  discolored  and  sluggish  in  its 
movements  and  much  swollen.  Kow,  this  exudate  I 
spoke  of,  in  some  forms  especially,  is  sticky,  adherent 


Fig.  46. 

in  its  nature,  and  is  the  cause  of  the  decided  adhesions 
between  the  lens  capsule  and  the  iris  {synechia).  This 
condition  may  be  readily  broken  up,  but  if  the  exudate 
is  of  an  organized  character,  i.e.,  vascular,  fibrous,  etc., 
then  the  adhesions  are  correspondingly  firm. 


88  VETERINARY    OPHTHALMOLOGY. 

Under  symptoms^  will  find  photophobia  and  lachry- 
niation,  frontal  pains  of  a  lancinating  nature,  which 
are  alioays  aggravated  at  night,  the  degree  of  pain 
being  some  indication  of  the  severity  of  the  case. 
The  lids  will  be  involved  to  some  degree,  usually 
but  slightly,  however.  Careful  examination  will  re- 
veal a  dull,  rusty  appearing  iris,  with  often  turbidity 
of  the  aqueous.  The  iris  from  infiltration  will  re- 
spond to  light  in  a  sluggish  manner.  There  Avill  be 
conjunctival  and  sub-con jnnctival  injection,  which  is 
represented  by  irregularly  scattered  vessels,  which 
may  be  moved  with  the  conjunctiva  by  rubbing  on  the 
lower  lid,  remember,  and  these  vessels  may  be  so  en- 
larged and  engorged  as  to  present  chemosis.  The  point 
wnll  be  the  rosy  zone  of  vessels  surrounding  the  cornea, 
of  a  delicate  pink — not  decidedly  red,  but  a  pretty  deli- 
cate pink.  The  lines  radiate  in  a  mathematical  manner, 
i.e.,  with  regularity  and  precision.  They  are  not 
affected  by  movement  of  the  lower  lid  with  the  finger  as 
are  the  conjunctival  vessels.  The  degree  of  this 
zone-like  injection  is  a  criterion  as  to  the  severity  of  the 
attack.  Adhesions  will  be  noticed,  and  may  be  slight 
or  very  pronounced,  from  a  slight  synechia  to  complete 
occlusion  of  the  pupil.  If  they  are  not  seen  or  easily 
diagnosed,  the  instillation  of  atropine  will  discover 
any,  no  matter  the  degree,  by  irregularities  of  the 
pupil.  (See  Fig.  46.)  Not  wise  to  expect  resolution 
this  side  of  six  weeks.     Maybe  met  within  one  or  both 


VETERINARY   OPHTHALMOLOGY.  89 

eyes.      The   one  condition,  

remember,  which  will  cause 
a  doubtful  prognosis  is 
si/nec/na,  otherwise,  with  a 
reasonably  robust  patient, 
the  prognosis  is  good. 
There  is  a  special  form  of 
iritis    called  purulent,   and  ^'^"  '^'' 

its  most  prevalent  cause  is  trauma.  Follows  opera- 
tions on  the  eye.  This  form  is  accompanied  by  the 
formation  of  pus  usually,  and  which  inay  be  in  such 
degree  as  to  collect  at  the  bottom  of  the  anterior 
chamber,  forming  hypopyon.  This  may  run  on  to 
panophthalmitis  or  general  suppuration  of  the  eye. 

Treatment. — Assure  yourself  that  no  exciting  cause 
remains  in  the  eye.  Then  atro2nne  till  full  mydriasis  is 
secured.  If  1%  be  not  strong  enough,  use  stronger  and 
stronger  solutions  until  the  effect  is  accomplished,  even 
to  the  crude  drug.  Then  maintain  it  by  a  weaker  solu- 
tion. The  patient  must  be  kept  quiet  in  darkened  stall 
and  not  overfed.  Cold  applications  are  the  most  recent 
and  successful  method  of  treatment  of  cases  with  rheu- 
matic com  plications.  But  in  using  very  cold  applications, 
watch  out  for  haziness  of  the  cornea,  when  they  must 
be  discontinued  (ITelfrich,  Schenck).  Now,  though  this 
seems  paradoxical,  warmth  is  a  valuable  means  of  treat- 
ment in  some  cases,  and  is  especially  valuable  in  re- 
lieving the  pain  at  night.    Let  it  be  d)->/  rather  than 


90      •  VETEEESTAEY   OPHTHALMOLOGY. 

moist  heat.  If  it  has  been  found  that  a  previously 
existing  synechia  is  an  exciting  cause,  an  iridectomy 
will  be  in  order,  and  also  later,  if  other  treatments  are 
ineffectual.  Of  course  the  underlying  cause  must  be 
cared  for,  whatever  it  may  be- 


Fig.48. 


Fig.  49. 

Tumors. — Not  much  to  be  done.  Simple  and  mali- 
gnant, as  met  with  elsewhere.  If  of  sufficient  import 
to  render  it  necessary,  excise  them.  Avoid,  if  possible, 
in  excising  cysts,  rupturing  their  walls,  if  of  a  serous 
nature,  for  the  serous  cyst  is  simply  distended  iris 
tissue,  and  is  translucent  in  appearance. 

There  is  a  condition  rarely,  very  rarely,  met  with, 
which  I  merely  mention,  called  Memhrana  Piipillaris 


VETERINARY   OPHTHALMOLOGY.  91 

Persistans.  During  gestation  the  pupil  is  closed  by  a 
membrane,  and  occasionally  some  part  or  all  of  it 
remains. 


Fig.  50. 


Iridectomy.— (Excision  of  a  portion  of  the  iris ;  re- 
moval of  the  entire  iris  is  iridavulsion.)     Iridectomy 


Fig.  51. 


demands  a  speculum,  fixation  forceps,  an  angular  or 
straight  keratome,  or  Grsetfe  knife,  iris  forceps  and 


92 


VETERINARY   OPHTHALMOLOGY. 


iris  scissors,  and  cocaine  4%.  Introduce  between 
the  lids  the  speculum.  With  the  fixation  forceps 
grasp  the  conjunctiva  directly  opposite  the  point 
of  incision  (on  the  opposite  side  of  the  cornea,  un- 
derstand), and  thus  control  the  eyeball.  (A  full 
dose  of  chloral  hydrate  is  good  in  irritable  patients). 
The  keratorae  is  inserted  about  a  line  from  the 
corneo-scleral  margin  into  the  cornea,  and  intro- 
duce the  blade  so  as  to  divide  as  little  tissue  as  pos- 


Fig.62. 

sible.  When  introduced  change  the  direction  of  the 
knife  so  as  to  avoid  touching  the  iris  or  lens.  With- 
draw knife  slowly  so  as  to  avoid  too  sudden  an  escape 
of  the  aqueous.  With  curved  iris  forceps  withdraw  a 
portion  of  the  iris,  having  grasped  it  at  its  pupillary 
edge.  Cut  it  off  with  the  scissors.  See  that  none  of 
the  iris  remains  in  the  wound.  Compress,  bandage. 
Maintain  asepsis  and  antisepsis,   and  instil  \  per 


VETEKINAKY   OPHTHALMOLOGY.  9B 

cent.  sol.  Eserine  immediately  to  draw  iris  away  from 
puncture  and  tlius  prevent  prolapse  or  synechia,  etc. 
Great  care  is  to  be  taken  not  to  injure  the  lens  or 
iris.  For  sliould  you  hit  tlie  lens,  cataract  is  apt  to 
ensue,  or  glaucoma,  with  its  horrible  consequences. 
The  cutting  of  the  iris  may  be  followed  by  a  little 
hemorrhage,  which  will  be  absorbed.  Be  guarded  also, 
in  withdrawing  the  keratome,  that  a  too  sudden 
evacuation  of  the  aqueous  does  hot  occur,  as  the  sudden 
diminution  of  intra-ocnlar  tension  might  be  followed 
by  hemorrhage  into  the  vitreous,  and  this  is  serious. 


CHAPTER  X. 


THE  CILIARY  BODY. 


Ciliary  Body. — Between  the  iris  and  the  ora  serrata. 
(anterior  limit  of  the  retina)  lies  the  ciliary  body,  which 
consists  of  the  ciliary  processes  and  muscles.  It  is  th& 
source  from  which  the  lens  and  vitreous  derives 
nourishment  largely.  Is  composed  ot  two  portions — 
(1)  a  muscular  and  (2)  a  pigmented  and  vascular  portion. 
Around  the  crystalline  lens  there  is  a  wide  black  circle^ 
the  ciliary  processes,  forming  regular  radiating  folds, 
which  project  by  their  inner  extremities  inward.  There 
are  about  120  of  these 
folds,  composed  of  connec- 
tive tissue,  which  is  con- 
tinuous with  that  of  the 
iris  and  pectinate  liga- 
ment; also  of  blood  ves- 
sels, convoluted,  and  cov- 
ered over  all  by  a  layer  of 
pigment.  From  the  fur- 
pjg  54  rows  that  separate  these 

processes  posteriorly  we  see  a  hyaline  structure  ex- 
tending, that  constitutes  the  zonule  of  Zinn,  which  goes 
94 


VETEEIN AE Y   OPHT  H AL:M0L0G Y. 
C. 


95 


Fig.  53. 

Ciliary  muscle,  after  Iwanoff ;  a,  cornea;  b,  corneal  limb;  c,  sclerotic; 
d,  iris ;  e,  Fontana's  Spaces. 


96  VETERINAKY   OPHTHALMOLOGY. 

to  the  border  of  the  lens  and,  dividing,  goes  to  each 
surface,  leaving  between  its  separating  surfaces  a  trian- 
gular space,  called  the  canal  of  Petit.  This  pectinate 
ligament  {Ligamentura  Fectinatwii)  is  that  portion  of 
connective  tissue  where  the  iris  is  joined  to  the  sclera 
at  the  edge  of  the  cornea.  The  suspensory  ligament  of 
the  lens  is  permeable,  transfusion  from  the  vitreous 
to  the  aqueous  taking  place.  Chauveau  says:  "The 
anterior  or  ciliary  zone  includes  two  parts  :  the 
'  ciliary  circle '  (or  ligament)  and  the  '  ciliary  body.' 
The  ciliary  circle,  ligament  or  muscle  {cmnulus  alhidus) 
varies  in  width  from  one  to  two  millimetres ;  its  external 
face  adheres  closely  to  the  sclerotic  and  its  internal  is 
confounded  with  the  ciliary  body;  the  posterior  border 
is  continuous  with  the  choroid  zone  near  the  canal  of 
Fontana  (ciliary  canal).  The  anterior  border  gives 
attachment  to  the  greater  circumference  of  the  iris." 
This  is  a  portion  of  Chauveau  which  I  will  explain  later, 
for  as  it  now  stands  it  is  not  over  easily  grasped.  To 
quote  still  further  :  "  The  ciliary  body  {corpus  ciliare) 
forms  a  kind  of  zone  or  ring,  wider  than  the  ciliary 
ligament,  and  consequently  overlaps  the  latter  before 
and  behind.  It  extends  on  one  side  on  the  inner  face 
of  the  choroid  and  on  tlie  other  on  the  posterior  face  of 
the  iris."  The  fibers  of  the  ciliary  muscle  are  of  the 
unstriped  variety,  and  in  different  parts  of  the  muscle 
they  take  different  directions,  the  whole  combined 
making  a   muscle   of  triangular   shape.     This  is  the 


YETERINAEY  OPHTHALMOLOGY.  97 


Fig.  55. 
Insertion  of  the  zone  of  Zinn  upon  the  crystalline  lens,  seen  from  in  front. 
The  pigment  of  the  detached  ciliary  processes  has  remained  adherent 
to  the  non-plicated  portion  (a)  of  the  zone  of  Zinn. 

muscle  of  accommodation.    Vessels  are  the  anterior 
7 


^8  VETERINARY   OPHTHALMOLOGY. 

and  posterior  ciliary,  which  come  from  the  ocular 
"branch  of  the  ophthalmic,  which  in  tarn  comes  from 
the  internal  carotid.  The  nerves  are  from  the  ciliary, 
which  contain  ganglion  cells  containing  sensitive,  motor 
and  sympathetic  filaments,  and  these  pass  to  ciliary 
body,  iris  and  cornea.  These  nerves,  you  understand, 
come  from  the  ophthalmic  division  of  the  fifth,  and 
the  fifth  is  peculiar  in  its  origin — to  wit.,  from  the  floor 
of  the  fourth  ventricle  and  side  of  the  pons  and  the 
Gasserion  Ganglion  (this  is  sensory),  and  from  the  floor 
of  the  fourth  ventricle  and  side  of  the  pons  for  its 
motor  root.  Contains  also  sympathetic  filaments.  The 
ophthalmic  branch  enters  by  the  sphenoidal  fissure. 

Cyclitis. — Inflammation  of  the  ciliary  body.  The 
ciliary  body  is  seldom  involved  alone.  Usually  the  con- 
tiguous parts  participate.  Is  as  a  rule  an  extension  of 
iritis ;  choroiditis.  If  the  result  of  operation,  or  injury, 
then  it  may  be  alone  involved . 

Under  tSi/mptoms  will  have  ciliary  injection  accom- 
panied by  chemosis,  pain.  The  eye  will  be  intolerant  of 
touch,  and  that  is  the  symptom.  The  iris  will  appear 
rusty.  This  may  go  on  to  inflammation  of  all  parts  of 
the  eye — jxinophthahmtis.     Prognosis  is  not  good. 

Treatment — .Hot  fomentations,  local  bleeding,  atro- 
pine, anodynes,  etc.  If  the  attack  prove  rebellious,  as  is 
often  the  case,  enucleation,  for  the  safety  of  the  other 
eye,  which,  through  sympathy,  may  participate.  Injuries 
are  dangerous,  principally  because  of  giving  origin  to 


VETERINARY   OPHTHALMOLOGY.  99 

sympathetic  ophthalmia.     So,  if  the  eye  be  injured  to 
-a  grave  degree,  enucleation  is  tlie  word. 

Irido-choroiditis^  Periodic  Opldhahnia^  Jflecciirrent 
Ophthahnia.,  Moon  hlindness^  {Irido-cyditis).  —  This 
iiffection  is  intimately  related  to  certain  climates; 
systems  and  soils,  and  shows  a  strong  tendency  to  re- 
cur again  and  again.  Usually  terminates  in  blindness 
from  cataract.  Its  causes  may  be  said  to  be,  primarily, 
in  the  soil — on  frequently  submerged  groiinds ;  on 
marshy  and  clayey  grounds ;  on  coasts.  Also  wet, 
damp  climates,  which  produce  lymphatic  constitutions. 
Again,  rank,  watery  foods.  This  affection  is  usually 
seen  during  the  dentition  and  breaking  period  ;  there- 
fore are  apt  to  see  it  between  two  and  five  or  six. 
Among  local  causes  would  be  smoke,  acrid  vapors,  dust, 
etc.  No  one  of  these  is  sufficient  to  cause  this  disease. 
To-day  a  microbe  is  the  alleged  cause,  or  the  product 
of  a  microbe.  This  product  may  be  preserved  in  the 
marshy  soil.  The  presence  of  a  definite  germ  has  not 
"been  demonstrated  as  yet. 

Heredity  is  one  of  the  most  potent  causes  we  know. 
This  is  very  positively  demonstrated  when  both 
parents  have  suffered.  In  support  of  this,  w^e  know  if 
a  mare  had  borne  a  number  of  foals,  all  sound,  and 
then  suft'ered  an  attack  of  periodic  ophthalmia,  the 
subsequently  born  would  also  suffer.  The  study  of 
atavism  presents  many  interesting  facts  in  these 
PAPitt^r'i.    An'']  yet  if  *,be  foals  of  diseased  parents  be 


100  VETEEINAEY   OPHTHALMOLOGY. 

transferred  to  high,  dry  ground  they  will  nearly  all 
escape.  In  France,  the  government  rejects  all  unsound 
stallions  and  refuses  service  to  any  mare  that  has 
suffered.  Unwholesome  food  and  errors  in  feed  are 
undoubtedly  predisposing  causes,  for  in  a  given 
district  those  fed  with  judgment  will  be  granted 
immunity  in  a  large  proportion  over  those  badly  fed. 
Intestinal  parasites,  over-work,  debilitating  diseases 
and  causes  of  every  kind  that  weaken  the  vitality. 

The  symptoms  vary  according  to  the  severity  of  the 
attack.  Some  present  marked  exacerbation  of  temper- 
ature, and  again  it  may  be  entirely  absent.  But  there 
uhmys  is  evidence  of  general  disorder,  lack  of  vitality. 
Locally,  symptoms  are  those  of  internal  ophthalmia 
with  the  addition  of  increased  tension  or  hardness  of 
the  bulbus.  This  may  be  due  to  effusion  into  its 
cavity.  The  contracted  pupil  does  not  expand  much 
in  darkness  nor  even  under  the  action  of  a  mydriatic. 
Opacity  advances  over  the  cornea  commencing  at  the 
limbus,  and  may  be  partial  or  complete.  And  so  long 
as  it  is  transparent  the  aqueous  will  be  seen  turbid, 
with  sometimes  floculi.  The  iris  will  appear  rusty 
and  dullish.  The  lens  will  be  clouded  and  will  observe 
a  greenish-yellow  reflection  from  the  eye.  From  the 
fifth  to  the  seventh  day  the  floculi  precipitates,  the  lens 
and  iris  are  more  plainly  seen,  and  the  commencing  ab- 
sorption may  be  complete  in  twelve  to  fifteen  days.  The 
recurrence  is  the  characteristic  of  the  affection.     And 


VETERINARY   OPHTHALMOLOGY.  101 

it  will  recur  again  and  again  and  in  the  same  eye  un- 
til total  loss  of  sight  ensues.  These  attacks  may  oc- 
cur at  intervals  of  a  month  or  so,  but  they  show  no 
relation  to  any  particular  phase  of  the  moon,  as  the 
name  would  lead  one  to  suppose.  These  recurrences 
are  determined,  more  likely,  by  some  periodicity  of 
the  system.  From  five  to  seven  or  eight  attacks  usu- 
ally suffice  in  resulting  blindness,  and  then  the  second 
eye  is  liable  to  attack  with  the  same  result.  Between 
the  attacks  some  latent  symptoms  tell  the  story,  and 
these  symptoms  become  more  marked  with  each  suc- 
cessive attack.  Even  after  the  frst  attack  there  can 
be  seen  a  bluish  ring  around  the  corneal  margin,  the 
eye  therefore  seeming  smaller  ;  and  after  several  attacks 
it  is  smaller  from  atrophy.  The  upper  eyelid,  in  place 
of  presenting  a  uniform  continuous  arch,  has  about 
one-third  from  its  inner  angle  an  abrupt  bend  caused 
by  the  contraction  of  the  levator  muscle.  The  pupil 
is  contracted  excei^t  in  advanced  cases,  where,  with  an 
opaque  lens,  it  will  be  widely  opened,  dilated.  The 
animal  will  carry  his  ears  erect  and  forward  to  com- 
pensate for  his  waning  vision.  Xow,  this  is  a  general 
picture,  but  that  the  attacks  vary  with  different  cases 
must  be  remembered.  The  recurrence,  however,  is 
characteristic,  and  all  alike  lead  to  cataract  and  intra- 
ocular effusion,  giving  rise  to  T  +,  with  pressure  on 
the  retina  and  resulting  blindness.  The  prevention  of 
this  disease  is  the  great  object,  and  to  accomplish  this 


102  VETERINARY   OPHTHALMOLOGY. 

most  desirable  end,  we  must  go  back  to  the  starting 
wire  and  have  careful  and  discriminating  breeding, 
feeding,  stabling,  etc.,  ad  infinitum. 

Treatment  is  unsatisfactory.  Some  are  benefited  by 
colchicum  in  scruple  doses  where  rheumatic  tendencies 
are  evinced,  or  two-dram  doses  of  salicylate  of  soda 
twice  daily.  If  the  tension  is  increased  to  a  marked 
degree  paracentesis  or  iridectomy  has  been  attended 
with  good  results. 

When  convalescing,  tonics — 

Oxide  of  iron,  x  3  ij. 

Nux  vom,  gr.  x. 

Sulphate  of  soda,  3  3.  daily. 

There  is  an  affection  of  the  eye  which  has  been  and 
is  the  subject  of  great  speculation  and  discussion : 


CHAPTER  XI. 

SYMPATHETIC  OPHTHALMIA. 

Sympathetic  Ophthalmia. — Supposed  to  be  due  to  a 
pre-existing  inflammatory  condition  of  tlie  other  eye.  At 
its  inception  there  is  some  photophobia,  some  injection 
and  laclirymation.  With  the  ophthalmoscope  will  lind 
opacities  floating  in  the  vitreous.  Pain  in  the  ciliary 
region,  especially  is  it  painful  to  touch.  The  hazi- 
ness of  the  aqueous  will  be  from  the  exudation  from 
the  ciliary  processes.  Occlusion  of  the  pupil  is  a 
common  accompaniment.  Tension  will  be  increased 
and  loss  of  sight  will  be  complete.  The  causes  which 
are  responsible  for  many  such  cases  are  injury,  trauma, 
especially  in  the  danger  zone,  i.  e.,  the  ciliary  region ; 
an  operation  for  cataract  with  the  incision  too  far 
back  of  the  corneo-scleral  margin,  for  instance; 
previous  inflammations,  followed  by  or  i-esulting  in 
atrophy,  etc.  The  period  of  danger,  /.  e.,  when  one 
eye  may  sympathetically  suffer  from  another,  is  vari- 
ously estimated  at  from  two  weeks  to  any  period. 
The  most  frequent  period  is  from  one  to  two  months- 
The  method  and  means  of  transmission  is  as  yet  an 
open  question,  and  space  forbids  entering  into  the  many 
103 


104 


VETERINAKY   OPHTHALMOLOGY. 


theories.  Prognosis  is  unfavorable,  especially  in  ani- 
mals, as  the  affair  is  well  established  and  effusion  has 
taken  place,  by  the  time  we  are  rendered  cognizant 
of  its  presence. 

Treatment. — Enucleate  the  exciting  eye,  and  if 
done  early  enough,  the  inflammation  will  be  checked. 
The  sympathetic  eye  must  be  treated  as  a  case  of  in- 
ternal ophthalmia;  to  wit,,  atropine  1  to  120.  Hot 
fomentations,  moist  or  dry,  as  you  choose,  etc. 


CHAPTER  XII. 

THE  CHOROID. 

The  Choroid  is  a  thin,  dark-colored  membrane  situated 
between  the  sclera  and  the  retina.  Extends  from  corpus 
cili  are  to  the  optic  nerve.  Made  up  of  vessels,  pigment, 
and  some  connective  tissue.  The  blood  comes  from 
the  short  posterior  ciliary  arteries  which  anastomose 
with  the  long  posterior  and  anterior  ciliary  arteries. 
The  veins  begin  as  capillaries  and  take  on  a  peculiar 
form.  Kesemble  as  much  as  anything  else  a  weeping 
willow,  and  these  uniting,  form  the  venae  vorticose, 
emptying  into  tlie  ophthalmic  vein.  The  anterior 
ciliary  vein  drains  the  anterior  portion.  The  long 
and  short  ciliary  nerves  form  plexuses  in  the 
choroid  and  contain  a  number  of  ganglionic  cells. 
Between  the  retina  and  choroid  there  is  a  layer 
of  pigmented  epithelium.  The  inner  face  of  the 
choroid  is  not  uniform  in  color,  being  perfectly 
black  in  the  lower  part  of  the  eye.  This  is  abruptly 
terminated  at  a  horizontal  line  about  the  eighth  or 
ninth  part  of  an  inch  above  the  optic  papilla.  From 
this  line  on  the  segment  of  a  circle  from  j*^  to  ^%  of  an 
inch  in  height,  it  shows  most  brilliant  colors;  at  first 
105 


106 


VETERINAKY   OPHTHALMOLOGY. 


blue,  then  an  azure-blue,  afterwards  a  brownish-blue, 
and  after  this  the  remainder  of  the  eye  is  occupied  by- 


Fig.  57. 
an  intense  black.     The  bright  portion  is  the  tapetum. 
The  Retina  lies  between  the  choroid  and  vitreous. 


VETERIMAltY   OPHTHALMOLOGY.  107 

Extends  from  the  optic  nerve  to  the  ciliary  processes, 
where  it  is  called  the  ora  serrata.  Consists  of  ten 
layers.  (1)  The  internal  limiting  membrane,  separates 
the  nerve  fiber  layer  from  the  vitreous,  and  the  fibers 
of  Miiller  terminate  in  this  layer.  (2)  IVie  nerve  fiber 
layer,  consists  of  the  axis-cylinder  of  the  optic  nerve 
fibers,  which  run  in  a  radiating  direction  to  the  ora 
serrata,  where  they  terminate.  At  the  macula  lutea 
these  fibers  are  bent  into  arches,  and  this  arrangement 
permits  a  larger  number  to  reach  the  yellow  spot  than 
if  they  approached  in  a  radiating  direction.  (3)  The 
layer  of  ganglion  cells,  composed  of  multipolar  cells, 
each  with  a  nucleus  and  nucleolus.  A  nerve  fiber  en- 
ters each  of  these  cells,  and  one  or  more  prolongations 
extend  out  into  the  inner  molecular  layer.  These 
ganglionic  cells  are  arranged  closer  around  the  optic 
nerve  than  at  the  ora  serrata.  (4)  The  internal  molecu- 
lar layer,  one  of  the  thickest,  granulous  in  appearance. 
Consists  principally  of  fine  fibers  from  the  layer  of 
ganglion  cells.  ('))  T/ie  infer/ud  granular  layer,  com.- 
posed  of  two  kinds  of  cells  with  nuclei.  The  larger  are 
nerve  cells,  having  tico  offshoots,  one  passing  into  the 
inner  granular  layer,  anastomosing  Avith  offslioots  of  the 
ganglionic  cells,  the  other  out  to  the  external  molecular 
layer  and  supposed  to  anastomose  with  fibers  from  the 
layer  of  rods  and  cones.  The  smaller  cells  of  this 
layer  are  connected  with  the  fibers  of  Miiller.  (0)  The 
external  molecular  layer.    Very  thin  and  is  made  up  of 


108  VETERINAPvY   OPHTHALMOLOGY. 

the  fibers  just  mentioned  with  some  molecular  matter. 
(7)  The  external  granular  layer.  Composed  of  both 
nerve  and  connective  tissue  elements.  Former  consists 
of  bi-polar  cells,  from  which  offshoots  pass  out  to  the 
rod  and  cone  layer  and  inward  to  the  internal  granular 
layer,  (8)  The  external  limiting  membrane^  formed  by 
the  terminal  extremities  of  Miiller's  fibers.  (9)  Tlie 
layer  of  rods  and  cones.  The  rods  commence  as  fine 
fibers  in  the  outer  molecular  layer,  pass  through  the 
outer  granular,  and  just  beneath  the  external  limit- 
ing membrane  begin  to  increase  in  size,  forming  the 
rod  granule,  and  some  distance  after  passing  through, 
this  membrane  they  taper  down  into  cylindrical-shaped 
rods  which  extend  outward  to  the  pigment  layer.  The 
cones  also  commence  as  a  cone-shaped  swelling  in  the 
outer  molecular  layer,  where  they  are  in  direct  commu- 
nication with  the  fibers  from  the  internal  granular 
layer.  The  cone  fiber  becomes  thinner  until,  just  un- 
derneath the  external  limiting  membrane,  it  again 
swells  rapidly  and  there  forms  the  cone  itself,  which 
contains  a  large  oval  nucleus  and  nucleolus.  The  cones 
are  shorter  and  thicker  than  the  rods,  and  are  of 
a  bottle-shaped  appearance.  The  rods  and  cones  are 
arranged  perpendicularly  to  the  plane  of  the  retina, 
and  may  be  divided  into  an  inner  and  outer  part.  The 
inner  is  thickest  and  appears  granulated ;  the  outer  is 
broken  up  into  highly  refracting  lamellae,  appearing 
like  superposed  discs  or  piles  of  coins.     (10)   The  2>ig- 


VETERINAIIY   OPHTHALMOLOGY, 


109 


ment  layer,  is  a  single  layer  of  hexagonal  nucleated 
cells,  the  inner  surface  of  which  is  loaded  with  pigment 


..au..| 


j-^ 


•sfcisi^asii^ 


Fig.  58. 
Section  of  Normal  Retina  X  350.-Eye  removed  for  Sarcoma,  Retina  de- 
tached  but  almost  normal.-l,  Vitreous ;  2,  hypertrophied  cells  of  vitre- 
ous ;  3,  membrana  limitans  interna  ;  4,  fibers  of  Muller  (they  are  slightly 
hypertrophied)— they  are  part  of  the  connective  tissue  frame  work  ;  5, 
layer  of  optic  nerve  fibers,  nuclei  more  numerous  than  usual  ;  6,  layer 
of  ganglion  cells,  some  of  them  having  undergone  colloid  degeneration  ; 
7,  internal  molecular  or  reticular  layer  :  8,  layer  of  inner  granules  ;  9, 
external  molecular  reticular  layer— in  this  as  in  the  internal  molecular 
layer  the  fibers  of  Miiller  are  abnormally  distinct ;  10,  layer  of  outer 
granules  ;  11  and  13,  layers  of  rods  and  cones,  in  which  a  distinction  is 
made  between  the  body  of  each  element,  11,  and  the  process  12,  which 
is  its  continuation  ;  13,  layer  of  epithelial  pigment  in  polygonal  cells.— 
{Xoyes). 

granules.    The  fibers  of  Muller  form  the  connective 


110  VETERINAEY    OPHTHALMOLOGY. 

tissue  framework  as  they  traverse  the  various  layers 
and  spread  out  in  its  membranes.  At  the  ora  serrata 
all  the  nerve  elements  disappear  and  the  connective 
only  continues,  forming  the  zonule  of  Zinn. 

The  Macula  lutea,  or  yellow  spot,  is  the  seat  of  most 
acute  vision.  The  macula  contains  no  rods,  while  the 
cones  are  longer  and  narrower  than  elsewhere.  At  the 
center  all  the  retinal  layers  are  thinned,  and  this  is  called 
VdQ  fovea  centralis.  The  retina  possesses  a  particular 
vascular  distribution.  The  arteria  centralis  retinae 
with  its  vein  enters  the  optic  nerve  at  a  short  distance 
from  the  globe,  and  xoith  it  passes  into  the  eye.  They 
traverse  the  papilla  and  immediately  divide  into  two 
branches,  one  up,  the  other  down.  These  branches 
then  turn  out,  but  none  of  its  capillaries  extend  into  the 
fovea.* 

Now,  though  the  choroid  and  retina  may  be  in- 
dependently  inflamed,  I  propose  to  describe  inflam- 
mation of  both  under  Internal  Ophthahnia.  Severe 
blows,  punctures,  foreign  bodies,  sudden  transition 
from  darkness  to  brilliancy,  glare  of  snow,  cold 
and  dampness,  high  winds,  (front  of  ferryboats,  for 
instance),  rain,  exposure  when  heated,  and  many 
general  diseases,  among  which  are  rheumatism  and 
influenza.  Met  with  during  dentition.  There  are 
not  many   external  symptoms,  unless   the  cause  was 

*  The  above  description  of  the  retina  was  taken  largely  front 
liforton's  excellent  work. 


VETERINARY   OPHTHALMOLOGY.  Ill 

external,  such  as  a  blow,  puncture,  etc.,  in  which 
case  the  lids  and  conjunctiva  would  participate  to 
a  marked  degree.  Otherwise  the  symptoms  would 
be  deep.  The  anterior  edge  of  the  sclerotic  where  it 
overlaps  the  cornea  will  remain  white,  when  posterior 
to  it  will  show  congestion ;  and  this  is  caused  by  the  fact 
that  the  arteries  (ciliary)  penetrate  the  sclera  behind 
its  anterior  border.  This  many  times  cannot  be  seen, 
owing  to  pigmentation.  The  opacity  of  the  cornea 
may  be  confined  to  its  outer  margin.  The  aqueous  will 
be  turbid  and  will  see  yellow-white  flakes  floating  in  it. 
These  may  deposit  and  form  hypopyon.  The  iris  will 
be  dull  and  rusty,  as  in  iritis.  Intense  photophobia. 
Watch  out  for  jldhesions.  In  taking  the  tension  will 
find  it  plus,  even  to  -j-  3.  In  severe  attacks  the  forma- 
tion of  pus  in  the  choroid  (and  iris),  which  escaping 
sinks  to  the  bottom  of  the  anterior  cliamber,  form- 
ing hypopyon,  as  above  stated.  In  nearly  all  cases 
cataract  results. 

Treatmext. — Quiet,  rest,  darkness.  May  give  a 
purge,  if  patient  is  robust.  If  any  rheumatic  ten- 
dency, colchicum,  3  ss  and  Sod,  salicyl,  3  ss,  daily. 
You  will  treat  the  eye  much  as  for  conjunctivitis. 
Astringents — Boric  ac.  4% ;  Zinc,  sulph.  one  to  two 
grs.  to  the  3 ,  and  jiever  forrjet  the  instillation  of 
atropine  1%,  using  an  eye  dropper.  Some  advise  use 
of  a  feather,  but  that  is  apt  to  carry  foreign  matters 
with  it,  so  don't.    In  cases  of  severe  pain,  cocaine  4%  is 


112 


VETERINARY   OPHTHALMOLOGY. 


good.  Local  bleeding  and  blisters,  the  bleeding  being 
accomplished  by  shaving  the  part  desired  and  apply- 
ing leeches. 

A  word  or  two  anent  the  Vitreous  humor.  It  oc- 
cupies all  that  portion  of  the  eye  behind  the  lens.  Has 
a  def)ression  in  front  called  the  lenticular  fossa  or  fossa 
patellaris  in  which  rests  the  crystalline  lens.  It  (the 
vitreous)  is  adherent  to  the  optic  nerve  and  ciliary  body 
and  has  no  other  attachments.  It  is  contained  in  the 
hyaloid  membrane,  and  this  membrane  forms  the  zonule 
of  Zinn,  and  it  is  between  the  layers  of  the  zonule  and 
around  the  circumference  of  the  lens  that  we  have  the 
canal  of  Petit.  Now  through  the  center  of  the  vitreous 
may  be  discovered  a  canal,  the  canal  of  Cloquet,  for  the 
hyaloid  artery  during  foetal  life.  This  is  sometimes  (very 
rarely)  seen  after  birth,  and  is  then  termed  Persistent 
Hyaloid  Artery,  and  it  has  no  attendant  vein.     The 

vitreous  humor 
has  neither  blood 
vessels  nor  ner- 
ves, but  it  must 
be  classed  with 
organized  struc- 
tures because  of 
the  cells  it  always 
contains.  These 
cells  have  no  de- 
F's-  59-  finite  form,  being 

round,  star,  spindle,  etc. 


CHAPTER  XIII. 

CRYSTALLINE  LENS. 

Crystalline  Lens. — A  transparent,  biconvex  body, 
solid  and  inclosed  in  a  membrane  which  is  transparent 
and  called  its  capsule.  According  to  Chauveau  the 
measurements  are  vertically  j\  of  an  inch ;  trans- 
versely yV-  The  posterior  face,  measuring  transversely 
■^,  is  the  more  convex,  for  the  anterior  transverse 
diameter  is  but  -^\j.  The  lens  is  enveloped  in  its  cap- 
sule but  nonadherent  to  any  part  of  it,  and  this  capsule 
is  of  uniform  thickness.  Is  composed  of  an  elastic 
homogeneous  membrane,  being  lined  anteriorly  with  a 
layer  of  cells  which  give  nutrition  to  the  lens.  The 
zonule  of  Zinn  or  suspensory  ligament  supports  the 
lens,  maintaining  it  in  its  position.  This  ligament, 
you  will  remember,  is  the  continuation  of  the  mem- 
brana  limitans  of  the  retina  which  passes  over  the 
ciliary  process  to  the  border  of  the  lens  and  separ- 
arately  passes  to  the  front  and  rear  of  the  capsule,  thus 
enveloping  it  and  making  a  capsule.  The  canal  of 
Petit,  you  see,  is  the  space  between  the  dividing  sur- 
faces and  the  circumference  of  the  lens.    Function  of 

this  canal  is  in  doubt ;  supposed,  however,  to  convey 
8  113 


114 


VETERINARY   OPHTHALMOLOGY. 


nourishment  to  the  lens.  The  zonule  has  control  over 
the  accommodative  changes  of  the  lens.  The  tissue 
proper  of  the  lens  is  composed  of  concentric  layers,  and 
each  layer  is  composed  in  turn  of  a  single  layer  of 


Fig.  60, 

Eye  of  calf— third  month  (Kolliker).  pp,  lower  lid;  pa,  upper  lid;  m,. 
mesoderm  not  yet  differentiated ;  c.  cornea;  mp,  membrana  papillaris; 
i,  place  of  iris ;  che,  chorio-capillaris ;  g,  vitreous ;  p,  pigment  layer  or 
proximal  lamella  of  the  secondary  eye  vesical;  r,  its  distal  lamella, 
composing  the  retina. 

fibers  with  a  cementing  substance.  These  fibers  have 
each  an  oval  nucleus.  Now,  each  fiber  runs  from  the  an- 
terior to  the  posterior  surface  in  a  meridianal  manner, 
the  ends  meeting  at  the  poles  of  the  lens  in  such  a 
manner  as  to  form  a  star-like  figure.    Taking  the  lens. 


VETERINAKY   OPHTHALMOLOGY.  115 

:as  a  whole,  it  is  divided  into  a  nucleus  and  a  cortex. 
A  single  layer  of  fibers  under  the  microscope  ■will  be 
seen  to  lie  parallel  and  each  measure  about  ^oVu  o^  ^^ 
inch  in  thickness.  They  unite  with  each  other  by 
serrated  borders,  by  dovetailing.  The  lens  acts  as  any 
plus  lens,  bringing  light  to  a  focus.  Cataract  is  the 
■common  result  of  internal  ophthalmia  and  is  an  opacity 


Pig.  61.  Fig.  62. 

of  the  crystalline  caused  by  interference  with  its 
nutrition.  Ergotism  is  a  cause,  but  we  don't  know  how. 
Clataract  may  occur  at  any  age.  Sometimes  congenital. 
Two  principal  divisions,  hard  and  soft  cataract. 
There  is  a  peculiar  form  called  mor(/a[/nian,  and  is 
a  hard  nucleus  or  a  fluid  cortex,  or  a  cataractous  lens 
floating  in  a  fluid  medium.  Traumatic  cataract  is 
a  soft  cataract  following  trauma.  The  detection  of 
cataract  is  by  oblique  illumination.  The  extraction  of 
the  cataract  will  not  improve  vision,  and  as  its  appear- 


116  VETERINARY   OPHTHALMOLOGY. 

ance  is  not  marked,  operative  interference  is  not  imper- 
ative. The  horse  would  be  a  shyer  after  removal,  as 
the  rays  of  light  would  not  he  focused  on  the  retina. 
Jteclination  or  depression  of  the  lens  into  the  vitreous 
has  been  done,  but  it  is  dangerous,  the  lens  being  apt  ta 
set  up  hyalitis,  etc. 

Ectopia  Lentis  or  dislocation  of  the  lens,  is  generally 
the  result  of  injury.  May  be  spontaneous  and  has  been 
congenital,  from  weakening  of  the  zonule  of  Zinn.  It 
may  also  be  complete  or  partial. 


CHAPTER  XIV. 

THE  OPTIC  NERVE. 

The  Optic  Nerve. — Of  this  we  will  have  but  little  to 
say.  The  anatomy  of  the  nerve  is  so  well  laid  clown 
in  Chauveau  and  the  various  works  on  anatomy  thab 
I  will  proceed  at  once  to  an  affection  called  Amaurosis 
(Ambhjopia).  Palsy  of  the  nerve.  The  term  amblyopia 
is  used  when  there  is  some  impairment  of  vision  for 
which  we  can  ascribe  no  cause.  Vision  is  often  thus 
defective  where  the  eye  has  long  been  disused — ambly- 
opia from  disuse  or  ex  anopsia.  In  anaemia  subsequent 
to  severe  illness  or  hemorrhages,  amemic  amblyopia. 
In  lead  poisoning.  From  exposure  to  prolonged  glare, 
as  in  snow-blindness.  From  irritation  of  the  fifth  pair, 
as  in  neuralgia ;  overdosing  with  quinine.  Also  tumors 
and  other  diseases  of  the  brain  implicating  the  roots  of 
the  optic  nerve.  Injury  to  the  nerve  between  the 
brain  and  eye.  Iletinitis.  Undue  pressure  upon  the 
retina  from  dropsical  or  inflammatory  effusion.  Also 
occurs  from  overloaded  stomach,  even  from  pressure  of 
the  gravid  uterus. 

Sywjytoms. — The  pupils  are  dilated  widely  and  do 

not  react  to  light.     A  feint  to  strike  does  not  cause  the 
117 


118  VETERINAEY   OPHTHALMOLOGY. 


Fig.  63. 


Scheme  of  the  Central  Visual  Apparatus.— R,  Retina,  shaded  where  It  l3 
Innervated  by  the  left,  clear  where  innervated  by  the  right  hemisphere  : 
No,  Optic  Nerve  ;  Ch,  chiasma ;  Too,  Tractus  Opticus ;  CM,  Melnerts 
commissure  ;  CG,  Guddens  commissure,  b,  lateral  tract  root ;  m,  median 
tract  root ;  Tho,  thalamus  opticus  ;  Cgl,  corpus  geniculatum  laterale ; 
Qa,  notes ;  Bqa,  brachia  anterior ;  Rd,  direct  cortical  tract  root ;  Ss, 
saggital  medullary  layer  of  occipital  lobe  ;  Co,  cortex  (chiefly  of  the 
cuneus) ;  Lm,  median  tract.— {Schleife). 


VETERINARY  OPHTHALMOLOGY.  119 

horse  to  swerve.  And  here  a  word.  In  making  these 
feints,  be  sure  you  do  not  cause  a  current  of  air  to 
strike  the  animal  which  would  cause  him  to  start  and 
so  possibly  deceive.  The  ears  are  held  erect  and  move 
quickly  on  appreciating  any  sound.  He  will  also  step 
high. 

Treatment  is  useful  only  when  the  disease. is  symp- 
tomatic of  some  removable  cause.  Should  the  condi- 
tion persist  after  the  subsidence  of  the  supposed  cause, 
try  blister,  (post  auricular,)  and  give  3  ss  doses  of 
nux  vomica  daily. 

Atrophy  of  the  Optic  Nerve.  This  may  be  the  oc- 
casion of  the  condition  above  described  and  (fig  64) 
is  to  be  watched  for,  especially  on  passing  horses.  So  it 
is  imperative  to  know  and  handle  the  ophthalmoscope 
intelligently.  The  general  symptoms  are  as  described 
under  Amaurosis.  Tlie  ophthalmoscopic  symptoms  are 
here  the  interesting  ones.  The  disk  is  almost  always 
white — decidedly  so — but  may  be  grayish,  and  the 
lamina  cribrosa  may  be  distinguished.  The  blood  sup- 
ply is  lessened,  witli  consequent  paleness,  and  the  larger 
vessels  will  be  lessened  in  caliber.  Thus  is  it  very  evident 
that  the  student  must  /oioto  the  appearance  of  a  normal 
fundus.  (See  colored  plate.)  Colored  crayons  and  a 
blackboard  will  not  convey  the  required  picture,  be 
they  ever  so  happily  depicted. 

The  disk  will  be  sharply  outlined,  and  often  this 
outline  will  be  pigmented.     If  this  atrophic  condition 


120 


VETERINARY   OPHTHALMOLOGY. 


succeeds  an  inflammatory  attack,  the  outlines  will  be 
ragged  and  ill-defined.  The  duration  of  a  case  of 
atrophy  is    tedious,  very,  months  and  years    being 


Fig  64. 

"usual  time  of  duration  of  a  case.    Occurs  at  all  ages 
and  may  be  congenital.     Prognosis  is  unfavorable. 

Treatment. — Little  or  none.    Strychnia  may  be  used, 
iypodermically,  about  the  temple. 


CHAPTER  XV. 

GLAUCOMA. 

Glaucoma. — Xortoii  defines  glaucoma  as  "an  excess 
of  pressure  "within  the  eye,  plus  the  causes  of  and 
consequences  of  that  excess."  That  place  where 
the  tissue  of  the  iris,  the  cellular  stroma  of  the  ciliary- 
body  and  the  posterior  and  external  portions  of  the 
cornea  and  sclera  intersect,  is  known  as  the  iritic 
angle  (see  fig.  53).  This  juncture  combines  to  make  a 
tissue  of  a  fenestrated  nature.  Tiiese  fenestra  or 
openings  are  the  Fontana  spaces.  The  meshes  of  this 
tissue  (just  imagine  a  coarsely  meshed  fisher's  net) 
merge  into  Descemet's  membrane  and  form  the  liga- 
ijiention  pectinaium  hidis.  In  the  sclerotic  is  formed, 
by  the  same  means,  the  canal  of  Schlemm  (see  fig.  42), 
and  all  of  these  spaces,  etc.,  are  connecting  and  are  of  the 
lymphatics.  The  caiial  of  Schlemm  communicates  with 
the  sclerotic  veins,  and  thus  the  connection  between 
the  anterior  chamber  and  the  circulation  is  established. 
Blood  is  never  found  in  these  spaces  physiologically. 
The  zonule  of  Zinn,  which  you   remember    extends 

from  the  ciliary  processes,  (posterior  surface)  to  the 
121 


122  VETERINARY   OPHTHALMOLOGY. 

lens,  is  a  readily  transfusible  membrane.  The  pres- 
sure in  the  aqueous  and  vitreous  are  equal,  and  this 
equilibrium  must  be  maintained  to  have  a  normal  eye. 
Tiie  slightest  excess  will  destroy  its  function  in  cor- 
responding degree.  This  equilibrium  is  rendered 
stable  by  due  secretion  and  excretion  of  the  fluids. 
The  intra-ocular  fluids  flow  from  the  blood  stream. 
The  ciliary  body  supplies  the  fluid  to  the  vitreous, 
aqueous  and  lens.  Most  of  the  secretion  passes 
directly  to  the  aqueous  by  means  of  the  pupil  and  filtra- 
tion angle.  A  very  much  smaller  portion  passes  back- 
ward and  out  through  the  papilla.  The  most  impor- 
tant change  v/hich  takes  place  in  glaucoma  will  be 
found  at  the  iritic  angle,  affecting  the  vessels  compos- 
ing or  entering  into  Schlemm's  canal.  These  are 
inflammatory,  and  the  iris  becomes  adherent  to  the 
cornea  and  closes  up  Fontana  spaces  partially  or  wholly, 
thus  hindering  the  excretion  of  the  fluids,  and  so  aug- 
ments the  condition.  The  fibers  of  the  optic  nerve 
become  inflamed,  and  atrophy,  in  the  later  stages. 
There  may  be  fluidity  and  detachment  of  the  vitreous 
and  cataract  of  the  lens. 

Symptoms. — Take  the  tension,  gently  palpating 
with  finger  tips,  using  both  hands,  and  it  may  be 
any  thing,  i.  e.,  -f  or  — .  Palpate  through  the  sclera 
back  of  the  cornea.  Cases  will  be  met  with  where 
the  tension  will  be  stony  in  its  degree  of  hard- 
ness.   Haziness  of  the  cornea  is  usually  present,  and 


VETERINARY   OPHTHALMOLOGY.  123 

the  cornea  will  also  present  anaesthesia.  Dilation 
and  inactivity  of  the  pupil  is  a  constant  symptom. 
The  word  glaucoma  means  green,  and  so  we  do  get 
a  greenish  reflex  in  glaucomatous  eyes.  The  pain  may 
be  slight  or  severe,  and  may  have  general  symptoms  of 
fever,  etc.  Swelling  of  the  lids,  chemosis  and  protru- 
sion (exopthalmus)  are  all  due  to  infiltration  from  pres- 
sure. Glaucoma  comes  in  relays,  /.  ^.,  have  a  prodromal 
stage  of  a  variable  duration,  weeks,  months  ;  and  then 
a  sudden  attack,  lasting  from  a  few  hours  to  days,  and 
then  the  eye  returns  to  normal  or  nearly  so.  These 
attacks  return,  and  the  intervals  become  shorter  and 
shorter,  and  finally,  chronic  or  a.bsolute  glaucoma.  Some 
cases  go  right  from  an  acute  to  absolute  with  no  re- 
batement  of  symptoms.  Glaucoma  tends  to  absolute 
blindness.  Any  condition  causing  vascular  turges- 
cence  may  cause  gout,  rheumatism,  fever.  The  use  of 
atropine  has  caused  it.  Prognosis  is  always  bad.  I 
had  the  pleasure  last  year  of  showing  the  class  a  caso 
of  Glaucoma  secimdarium  in  one  of  the  clinics.  One  of 
the  patients  from  the  Broadway  car  stables  was 
pointed  out  to  me  as  having  an  interesting  eye,  and  so 
it  was.  Secundarium  means  increased  intra-ocular 
tension,  consequent  to  some  other  disease.  This  case 
presented  total  occlusion  of  the  pupil,  the  pupil  being 
fast  completely  around  to  the  lens  capsule.  (See  Fig. 
47.)  The  eye  was  buphthalmic and  hydrojyhthalmic.  The 
whole  globe  was  enlarged,  and  the  cornea  especially  was 


124  VETEEINAEY   OPHTHALMOLOGY. 

distended,  resembling,  indeed,  a  soap-bubble.  The  lens 
might  have  been  of  ground  glass  for  all  its  transpar- 
ency.   Nothing  could  be  done. 

I  have  said  Atropine  has  caused.  Since  then,  in- 
vestigations have  led  to  the  use  of  Scopolamine  Hydro- 
bromate,  which  we  have  reason  to  believe  does  not  in- 
crease intraocular  tension.  Therefore,  use  in  place  of 
Atropine  (in  strength  1  to  200)  wherever  have  cause 
to  suspect  «;iy  t?icrease  in  tension.  Another  point.  In 
making  up  collyria,  use  Trikresol  1  to  the  1000  (in 
place  of  distilled  water  only  as  this  will  not  decompose 
and  is  harmless  to  the  eyes). 

Teeatment. — The  only  medicinal  remedy  is  Eserine 
Sulph.  ^%  every  couple  of  hours,  and  must  be  used 
early.  In  veterinary  practice  the  opportunity  to  use 
it  does  not  occur,  as  the  condition  is  well  advanced  by 
the  time  it  is  diagnosed.  The  eserine,  you  know,  will 
ontract  the  pupil  and  thus  tend  to  freeing  the  iritic 
angle.  Also  constricts  the  vascular  system,  diminish- 
ing secretion. 

Dovbt  use  atropine.  Iridectomy^  introduced  in  '57  by 
Von  Graefe,  is  the  operation  for  glaucoma.  The  incision 
should  be  in  the  sclera,  and  allow  the  aqueous  to  drain 
away  gradually^  and  be  sure  that  no  remnants  of  the 
iris  remain  in  the  wound.  The  eye  is  not  exempt  from 
parasites,  and  we  meet  with  Acari  (mites),  and  nothing 
need  be  further  said,  as  you  all  know  of  them  and  have 
suffered  from  their  getting  in  the  eye. 


TETEEINAEY   OPHTHALMOLOGY.  125 

Filaria  lachrymalis.— A  white  worm,  about  an  inch 
in  length,  found  in  the  lachrymal  duct  and  under  side 
of  the  eyelid  and  meinbrana  nictatans.  Their  presence 
sets  up  a  conjunctivitis  spoken  of  as  a  vermi?ious  con 
junctivitis.  Remove  and  treat.  Filaria  papulosa. 
A  silvery  delicate  worm,  about  two  inches  long.  Seen 
in  the  aqueous  and  is  very  active.  This  was  Barnum's 
famous  "  Snake  in  the  Eye."  Sets  up  inflammation  and 
has  to  be  removed.  Best  to  make  incision  in  upper 
half  of  cornea  near  the  scleral  border.  Then  treat 
the  inflammation.  The  Echinococciis,  the  larval  state 
of  the  tape- worm  of  the  dog  has  been  found  in  the  eye. 

Cysticercus  has  its  origin  between  the  choroid  and 
the  retina,  and  causes  detachment  of  the  latter,  finally 
perforates  it  and  enters  the  vitreous,  and  entering  the 
vitreous,  sets  up  an  irido-cyclitis  and  goes  on  to  de- 
struction of  the  eye. 

Pentastoma  Taenioides  has  been  found  by  Stitten  ia 
the  horse's  eye,  but  this  case  stands  alone. 


CHAPTER  XVII. 

ENEUCLEATION. 

Eneucleation. — Instruments  necessary  will  be 
curved  blunt-pointed  scissors,  speculum,  fixation  for- 
ceps and  a  strabismus  hook.  The  administration  of 
cUoral  hydrate  in  full  doses,  and  also  cocaine 
4  per  cent.,  is  necessary  to  this  ox^eration. 
Separate  at  the  corneal  margin  the  conjunctiva 
from  the  globe,  going  completely  around,  of  course. 
Then  divide  the  attachment  of  the  superior  straight, 
after  catching  it  on  the  strabismus  hook.  Have  an 
assistant  hold  the  wound  open  with  this  hook,  while 
you  take  another  and  insert  it  under  the  insertion  of 
the  internal  straight,  and  so  proceed  with  the  balance 
of  the  muscles.  Some  divide  the  obliques  previous  to 
the  optic  nerve,  and  others,  the  reverse — protruding 
the  eye  by  pressure — dividing  the  obliques  and  then 
the  nerve.  Do  whichever  method  comes  the  more 
natural  to  you,  and  as  the  exigencies  of  the  case  pre- 
sent. With  the  scissors  closed,  push,  probe  and  sepa- 
rate your  way  back,  until  the  nerve  is  reached  on  the 
inner  side,  and,  with  one  cut,  divide  the  nerve.  Will 
have  an  immediate  flow  of  blood,  which  is  easily  con- 
trolled by  pressure.  This  operation  is  followed,  as. 
12G 


VETERINARY   OPHTHALMOLOGY. 

may  be  easily  imagined,  by  considerable  reaction,  some- 
times fatal.  There  is  a  method  ascribed  to  Liebold 
which  is  followed  by  less  reaction  and  is  called  Exen- 


127 


Fig.  GO. 


Fig.  68, 


teration,  and  consists  in  opening  the  eye  by  excising 
the  cornea  at  its  limbus  and  removing  the  entire  con- 
tents.   When  these  cases  have  been  fatal,  has  been  by 


128  VETERINARY   OPHTHALMOLOGY. 

meningitis  mostly.  Still,  with  ascepsis  and  antisepsis 
closely  observed,  there  need  be  no  hesitation  in  per- 
forming this  operation. 

A  word  or  two  anent  the  Ophthalmoscope  and  its 
use.  This  instrument  was  the  result  of  long  and  care- 
ful investigation  by  Professor  11.  Ilelmholtz  of  Berlin. 
Was  introduced  to  the  scientific  world  in  1851.  The 
scope,  as  it  exists  to-day,  consists  of  a  mirror,  either 
plane  or  concave,  with  a  perforation  called  the  sight 
hole.  Also  generally  there  is  an  object  lens.  The 
mirror  is  the  essential.  Usually  we  use  a  lamp  for 
light,  and  have  it  held  behind  and  to  one  side  of  the 
eye  Ave  wish  to  examine.  The  examiner  should  keep 
both  eyes  open,  for  the  same  reason  that  a  sailor  will 
keep  both  open  when  using  the  telescope,  and  what- 
ever may  be  seen  by  the  other  eye  must  be  disregarded. 
The  first  thing  noticed  will  be  a  ref?  reflex,  where  before 
the  introduction  of  the  beam  of  light  all  seemed  black. 
Having  succeeded  this  much,'  the  student  will  try 
and  make  up  his  mind  finally  that  this  particular 
eye  has  no  disc,  hut  it  is  there,  and  that  is  the  objective 
point.  Find  the  disc.  Just  when  one  decides  to  "  let 
go"  and  postpone  the  search,  like  a  moon  in  a  brilliant 
sky,  the  disc  will  sail  into  sight,  and  as  quickly  sail 
out  of  view.  However,  we  have  demonstrated  to  our  own 
satisfaction  that  it  is  there,  and  that  gives  one  the  needed 
stimulus  to  go  on  and  patiently  endure  disappointment 
after  disappointment,  until,  as  always,  success  crowns 


VETERINARY  OPHTHALMOLOGY. 


129 


our  efforts  and  we  are  astonished  and  pleased  with  our 
ability  to  locate  the  disc  and  study  its  condition  at  will. 
We  cannot  tell  our  patients  to  look  upward,  down- 


Fig.  69. 

ward,  to  the  right,  to  the  left,  and  thus  bring  into  the 
field  each  and  all  portions  of  the  fundus.     Therefore 
ine  do  the  see-sawing,  and,  having  gotten  the  focus, 
9 


130  VETEEINARY  OPHTHALMOLOGY. 

slide  your  head,  (and  with  it  your  eye)  vnth  the  scope 
in  position,  to  tlie  right  and  left,  upward  and  down- 
ward. There  are  two  methods  of  examining  the 
fundus — direct  and  indirect.  In  the  direct  method, 
the  image  (tliat  which  we  see  and  appreciate,  at  the 
bottom  or  fundus  of  the  eye,  is  the  image),  will  be 
erect,  i.  e.,  it  will  have  suffered  no  inversion,  as  is 
the  case  when  the  indirect  method  is  employed, 
for  there  we  interpose  a  biconvex  lens  between  the 
eye  examined  and  our  own,  thus  inverting  the  image 
This  I  demonstrated  early  in  the  session  upon  the 
blackboard  diagrammatically.  Now,  if  you,  for  experi- 
ment, will  take  a  piece  of  card- board  and  drive  a  pencil 
through  it,  you  will  tind  on  looking  through  the  result- 
ing hole  that  the  nearer  your  oicn  eye  you  bring  the 
card  the  larger  will  be  the  field  of  vision.  Yes?  So 
with  the  eye  of  the  subject,  for  the  pupil  represents 
the  hole  in  the  cardboard.  But  there  is  a  bar  here 
which  can  be  overcome  only  by  experienced  pilots. 
The  observer  must  put  his  own  eye  in  a  condition 
equivalent  to  his  looking  at  an  object  in  the  distance 
— twenty  feet — i.e.,  his  eye,  to  see  the  fundus  (the  ac- 
commodation of  the  observed  eye  being  suspended,  at 
rest)  must  be  in  a  condition  to  receive  parallel  rays. 
Fortunately,  the  horse  under  examination  being  in  a 
semi-darkened  room,  relaxes  his  accommodation,  and 
thus  one  factor  is  overcome.  This  is  to  be  accom- 
plished only  by  2^f'cictice,  and  like  all  good  things  is 


VETERINARY   OPHTHALMOLOGY.  131 

gained  only  by  patient  application.  The  observer's 
eye  must  be  normal,  i.e.,  neither  hyperopic,  myopic  or 
astigmatic,  and  if  such  conditions  do  exist  they  must 
be  corrected  by  a  proper  glass.  The  indirect  method^ 
{the  inverted  imar/e.)  To  use  this,  the  examiner  holds 
in  front  of  the  observed  eye  a  biconvex  lens  of  2.} 
or  3^,  inch  focus,  and  does  not  bring  the  scope  nearer 
than  one  foot,  and  he  may  draw  gradually  back 
until  the  proper  view  is  obtained,  the  top  of  the  scope 


# 


cu    b  c 
Fig.  ri. 

touching  the  eyebrow.  This  biconvex  lens  condenses 
the  light  v.iiich  the  mirror  throws  to  the  eye,  and  of 
necessity  (light  returning  in  the  same  direction  in 
Which  it  came)  passes  through  the  lens,  becoming- 
inverted  and  forming  an  image  hetireen  the  lens  and 
mirror,  in  the  air,  and  is  thus  an  aerial  image.  An  im- 
portant aid  to  diagnosis  is  the  2J  inch  lens  which 
accompanies  the  ophthalmoscope,  and  which  we  use  in 
tlie  indirect  method,  and  also  for  oblique  illumina- 
tion. In  oldeu  times,  before  oblique  illumination, 
the  catoptric  test  was  used  to  detect  cataract, 
etc.,  in  the  lens,  but  where  it  was   most    desir- 


132  VETERINARY   OPHTHALMOLOGY. 

able,  i.e.,  in  the  very  obscure  and  slight  cases,  it  was  of 
little  use.  It  is  still  useful  in  determining  the  presence 
or  absence  of  the  lens,  and  depends  upon  the  fact  that 
the  surfaces  of  the  cornea  and  lens  reflect  images  and 
consists  of  the  following  maneuvres :  Hold  a  candle, 
lighted,  '.efore  an  eye  in  a  darkened  room,  and  you  will 
observe  three  distinct  images — the  anterior,  bright,  erect 
and  distinct  from  the  anterior  surface  of  the  cor)iea  ;  an 
intermediate,  slight,  smaller,  inverted,  and  fairly  dis- 
tinct from  the  lens'  posterior  capsule,  which  is  con- 
cave ;  and  a  posterior,  indistinct  and  erect  from  the 
surface  of  the  len£  anterior  capsule.  To  return  to 
oblique  illumination,  and  this  is  of  extreme  applica- 
bility. While  being  very  easy,  the  veriest  novice  hav- 
ing it  at  his  conmiand,  it  is  decidedly  thorough,  one 
being  enabled  by  its  mediation  to  discern  the  slightest 
opacities  and  strise  of  incipient  cataract,  etc.  For  this 
test,  need  but  a  2J  inch  lens  and  a  candle  flame.  To 
be  thorough,  the  use  of  cocaine,  atropine,  or  scopo- 
lamine is  necessary.  Have  the  candle  placed  on  one 
side  of  the  head  and  concentrate  its  rays  by  means 
of  the  lens  so  as  to  focus  upon  the  eye,  and  then  the 
cornea,  the  pupil,  the  iris  and  the  lens  may  be  very 
thoroughly  studied.  For  the  examination  of  the 
anterior  parts  and  chamber,  the  lens  is  suflBcient, 
but  there  it  ends  and  the  ophthalmoscope  comes  into 
play.  If  we  take  a  small  box  and  punch  a  hole  in  the 
top,  through  which  we  send  a  pencil  of  light  by  means 


YETERINArvY   OPHTHALMOLOGY.  133 

of  our  2i  inch  lens,  we  illuminate  the  interior,  and  can 
study  its  every  part.  "Well,  then,  why  not  the  same 
with  the  eye  ?  The  eyeball  is  not  a  box  simply.  It 
contains  a  lens,  and  that  is  why.  If  you  throw  a 
pencil  of  light  into  the  eye  it  will  be  brought  to  a  focus 
by  the  lens.  That  is  not  the  case  in  a  simple  box. 
Tlie  light  has  to  come  back  again  and  emerge  from 
the  eye.  So  if  the  lens  (biconvex)  brings  the  entering 
rays  to  a  focus,  it  does  the  same  for  those  emerging. 
(See  figs.  G  and  7.)  But  the  entering  rays  were  parallel 
and  brought  to  a  focus  through  the  mediation  of  the 
lens,  whereas  the  emerging  rays,  coming  from  a 
focus,  were  rendered  parallel.  Let  us  go  a  little 
furtlier.  Suppose  divergent  rays  be  the  case,  as 
they  will  pass  to  the  lens  and  on  returning  will  be 
converged  and  made  to  meet  at  a  focus  in  front  of  the 
lens.  As  the  rays  primarily  were  not  parallel,  but 
divergent,  the  focus  at  which  they  meet  after  passing 
through  the  lens  will  not  be  at  the  same  distance,  as 
you  see.  They  will  be  further  than  the  focus  for 
parallel  rays.  If  one  of  tlie  foci  be  brought  nearer  the 
lens  the  otlier  will  be  further  off  and  are  called  con- 
jugate foci.  Xow,  please  notice  that  although  con- 
jugate they  maintain  a  certain  distance  between  each 
other,  for  as  you  approach  one  foci  the  other  recedes. 
So,  all  rays  emanating  from  the  eye  take  a  direction 
toward  the  conjugate  focus,  and  if  one  attempts  using 
this  ray  to  see  the  fundus  he  must  necessarily  bring 


134  VETERINARY   OPHTHALMOLOGY. 

his  eye  into  their  line.  Tlien  what  happens?  The 
line  occupied  by  these  rays  is  the  same  that  was  taken 
by  the  entering  rays,  and  if  no  rays  enter  the  eye,  none 
will  emerge.  And  when  you  try  to  intercept  the  rays 
coming /rom  the  eye  so  as  to  make  use  of  them  in  view- 
ing the  fundus,  you  get  in  the  path  of  the  lines  of  light 
which  enter  and  of  course  your  head  intercepts  them. 
Consequently,  having  cut  off  the  source  of  light,  the 
result  is  darkness.  For  example,  a  candle  a  couple  of 
feet  from  the  eyes  will  give  divergent  rays,  which  will 
enter  the  eye,  be  refracted  and  focus  on  the  retina, 
forming  an  image  of  the  candle-flame.  The  rays  will 
undergo  reflection,  and  being  reflected  back  through 
the  lens,  will  be  again  refracted,  and  you  will  find  at 
the  candle-flame  an  image  of  the  fundus,  and  at  the 
candle-flame  is  one  of  the  conjugate  foci.  Of  course,  if 
you  interpose  your  head  between  the  eye  and  the  candle, 
the  rays  emanating  from  the  candle  will  be  cut  ofl:  and, 
in  place  of  the  observed  eye  being  illuminated  it  will 
be  in  a  shadow  of  your  own  head.  If  you  try  to  look 
from  the  other  side  of  the  flame,  i.  e.,  having  the  flame 
between  you  and  the  patient's  eye,  you  will  be  dazzled  by 
the  flame,  as  it  radiates  light  in  all  directions  though 
in  straight  lines.  And  there  the  matter  stood  until, 
in  1851,  Helmholtz,  after  careful  study  evolved  the 
Ophthalmoscope.  "What  was  wanted  was  a  some- 
thing which  would  allow  an  observer  to  bring  his 
head  into  his  own  light.    This  the  mirror,  which  is  a 


VETERINARY   OPHTHALMOLOGY. 


135 


part  of  the  ophthalmoscope,  does,  being  a  mirror 
pierced  by  a  hole  for  observation.  An  ophthalmoscope 
consists  principally  of  two  parts— a  mirror  and  a  lens, 
and  the  mirror  is  the  essential  part,  everything  else 
being  accessory. 

"  Find  out  the  cause  of  this  effect. 
Or  rather  say  the  cause  of  this  defect, 
For  this  effect  defective  comes  by  cause." 

Hamlet. 

FINIS. 


INDEX  OF  ILLUSTRATIONS. 


PACE. 

Action  of  ocular  muscles 47 

Apparatus,  lachrymal 38 

Agnew's  canaliculus  knife 41 

Anterior  staphyloma    69,  77 

Abscess,  corneal 73 

Accommodation 83 

Angle  of  incidence 8,9 

Angle  of  reflection 8,  9 

Anterior  portion  and  ciliary  region 13,  82 

Angular  keratoma 90 

Artery,  persistent  hyaloid 113 

Body,  ciliary 82,  94 

Cowman's  probes 43 

Corneal  cells 66 

Corneal  abscess 73 

Clamp  forceps 37 

Canals,  hygrophthalmic 38 

Canaiiculi 38 

Canaliculus  knife,  Agnew's 41 

Ciliary  body 82,  94 

Cornea 83 

Canal,  Schlemm's 83 

Circular  fibers  of  ciliary  muscle 8.?- 

Ciliary  muscle,  circular  fibers  of 83 

Crystalline  lens 82,  115 

137 


138  INDEX  OF  ILLUSTRATIONS. 

PAGE. 

Cells,  corneal 66 

Cells,  pigment,  of  iris 85 

Corpus,  eiliare 94 

Ciliary  processes 94 

Ciliaiy  muscle 95 

Cornea 95 

Colored  plate .Frontispiece 

Choroid 104 

Ciliary  region 13,  83 

Cell,  pigment,  of  retina 14 

CJavity,  orbital 19 

Cartilages,  tarsal 27 

Coat,  choroid - 104 

Cells,  ganglion 109 

Central  visual  apparatus 118 

Catoptric  test 131 

Candle  test 131 

Decomposition  of  light 12 

Dilator  pupillae 86 

Duct,  nasal 38 

Disc 120 

Eye,  third  month 114 

External  molecular  layer  of  retina 109 

Eye  of  calf  at  third  month 114 

Embryological  eye 114 

Enucleation  scissors 127 

Eyelid,  saggital  section  of  upper 25 

Eye,  muscles  of 46 

Eye,  general  scheme  of  (tailpiece) 80 

Formation  of  image 4 

Foci  of  rays 10,  11 

Fontana's  spaces 83 


INDEX  OF  ILLUSTRATIONS.  139 

PAGE. 

Fibers,  meridianal,  of  ciliary  muscle 82 

Fibei*s,  radiating,  of  ciliary  muscle 82 

Forceps,  fixatiou 75,  90,  127 

Fontana's  spaces 95 

Forceps,  iris 90 

Fibers,  circular,  of  ciliary  muscle 82 

Fibers  of  Muller 109 

Fixation  forceps 75,  90,  127 

Fixation  speculum 127 

Forceps,  trachoma 59 

Forceps,  clamp 37 

Gland,  lachrymal 38 

General  scheme  of  the  eye 80 

Ganglion  cells 109 

Hyaloid  artery,  persistans 112 

Hook,  strabismus 127 

Hypopyon 72 

Hygropthalinic  canals  or  lachrymal  ducts 38 

Image,  inverted 17 

Iris 82,  95 

Iris,  pigment  cells  of So 

Iritis 87 

Iris  forceps 00 

Iris  scissors 91,  92 

Iridectomy 91 

Insertion  of  zonule  of  Zinn 97 

Inverted  image 17 

Internal  molecular  layer  of  retina 109 

Internal  granular  layer  of  retina 109 

Jaeger's  keratorae 90 

Jones-Wharton,  operation  of 35 

Knife,  Agnew'scaiinliculiis 41 


140  INDEX  OF  ILLUSTRATIONS. 

Knife,  Stilling's 43 

Keratitis,  phlyctenular 71 

Knife,  Saemische's 75 

Keratome 90 

Lachrymal  ducts  or  hygrophthalmic  canals 38 

Lid,  saggital  section  of  upper 25 

Ligament,  pectinated 82 

Layers  of  retina 106 

Layer  of  optic  nerve  fibers 109 

Layer  of  rods  and  cones 109 

Lens,  crystalline 82,  115 

Loring's  ophthalmoscope 129 

Lid,  vertical  section  of  upper 34 

Lachrymal  apparatus 88 

Lachrymal  gland 38 

Lachrymal  sac 38 

Muscles  of  eye 46 

Muscles,  scheme  of  action  of  ocular 47 

MuUer,  fibers  of 109 

Muscle  of  accommodation 82 

Meridianal  fibers  of  ciliary  muscle 82 

Muscle,  ciliary 95 

Nerve,  optic 118 

Normal  fundus  of  eye Frontispiece 

Normal  retina,  section  of 109 

Nasal  duct 38 

Ocular  muscles,  scheme  of  action 47 

Onyx : 72 

Operation,  Wharton-Jones 35 

Optic  nerve  fibers,  layer  of 109 

Outer  granular  layer  of  retina 109 

Optic  nerve 118 


INDEX  OF  ILLUSTRATIONS.  141 

PAGF. 

Of-tic  disc 1'20 

Ophthalmoscope -129 

Ora  serrata 83 

Occlusion  of  pupil 85* 

Orbital  cavity 19 

Operation  for  ptosis 33 

Pencil  of  rays  of  light 9 

Prismatic  spectrum 12 

Pigment  cell  of  retina 14 

Ptosis,  operation  for 32 

Pectinated  ligament 82 

Pigment  cells  of  iris 85 

Pupil,  spliincter  of 86 

Posterior  synechia 89 

Pupil,  occlusion  of 89 

Pupil,  dilator  of 86 

Processes,  ciliary 94 

Pigment,  epithelial  of  retina 109 

Persistent  hyaloid  artery 112 

Pterygium  62 

Phlyctenular  keratitis 71 

Puncta 38 

Probes,  Bowman's 43 

Retina,  reticular  layer  of 109 

Retina 106 

Retina,  section  of  normal 109 

Reticular  layer  of  retina 109 

Ring,  tendinous,  of  ciliary  muscle 82 

Retina,  internal  molecular  layer 109 

Radiating  fibers  of  ciliary  muscle 82 

Retina,  inner  granular  layer 109 

Refracted  ray  of  light 7,  9 


142  INDEX  OF  ILLUSTRATIONS. 

PAGK. 

Retina,  external  molecular  layer ll'J 

Region,  ciliary 13,  8'3 

Retina,  pigment  ceil  of 14 

Retina,  outer  granular  layer 109 

Rods  and  cone  layer .109 

Retinal  layer  of  epithelial  pigment 109 

Scheme  of  the  central  visual  apparatus 118 

Scissors,  Enucleation 127 

Schleram's  canal 83 

Section,  sagittal,  of  upper  lid 25 

Space,  Fontana's 82,  95 

Strabismus  hook -127 

Section  of  normal  retina 109 

Synechia 87 

Speculum,  fixation 127 

Serrata,  ora 82 

Sphincter  pupillae 86 

Synechia,  posterior 89 

Scissors,  iris 90 

Spaces,  Fontana's 82,  95 

Scheme  of  accommodation 6 

Seven  primary  colors 12 

Spectrum,  prismatic  12 

Sagittal  section  of  upper  lid 25 

Section,  vertical  of  upper  lid 34 

Symblepharon 36 

Sac,  lachrymal 38 

Stilling's  knife 43 

Scheme  of  action  of  ocular  muscles 47 

Staphyloma,  anterior 69,  77 

Spring  speculum '^5 

Saemische's  knife -75 


IXDEX  OF  ILLUSTRATIONS.  143 

PAGE. 

Speculum,  spring 75 

Scheme,  general  of  the  eye 80 

Tarsi 38 

Trachoma  forceps 59 

Tendinous  ring  of  ciliary  muscle 82 

Tarsi 27 

Third  month,  eye  at 114 

Test,  catoptric 131 

Tailpiece 136 

Test,  candle 131 

Upper  lid,  saggital  section  of, 25 

Upper  lid,  vertical  section  of 34 

Venae  vorticosae 104 

Vitreous 109 

Vertical  section,  upper  lid .34 

"Wharton-Jones  operation .35 

Zonule  of  Zinn 82,  97 


INDEX 


PAGi:. 
Annulus  albidus 96 

Accommodation 7,  14,  97 

Arteria  centralis  retinae 79,  110 

**       hyaloid 112 

Acari 124 

Angle,  iritic 121 

Abrus  precatorius 58 

Abscess  of  cornea 72 

Anteria  synechia 73 

"      capsular  cataract 73 

Annular  staphyloma  of  Sclera 83 

Agnew 41 

Abscess  of  lids 30 

Anchyloblepharon 36 

Axis,  optic 16 

Artery,  Ophthalmic 21 

Anf;;!e  of  reflection 8 

'*      "     incidence 8 

Axis,  Chief 10 

Aberration,   spherical 11 

Aqueduct  of  Sylvius 15 

Amaurosis 117 

Amblypia 117 

Atrophy  of  optic  nerve 119 

Blindness,  snow 117 

Bibliography 137 

145 


146  INDEX. 

Body,   ciliary o .  .94 

Blindness,  moon 99 

Euphthalmus 83 

Blenorrhoea 54 

Bean,  Jequirity .  .58 

Bowman's  membrane 65 

Burns  of  cornea 68 

Bleijhafitis,  acute 30 

"  ciliaris 31 

"  marginalis 31 

Blepharospasmus 33 

Blejiharophimosis 33 

Burns  of  lids 37 

Bulbus 15,  16 

Baptista  Porta 6 

Binocular  vision 7 

Color 17 

Cavity,  orbital 19 

Chauveau 19,  96,  113 

Capsule,   Tenon's 21 

Cellulitis,  orbital 23 

Canaliculi 24,  39 

Ciliary  muscle  of  Riolini 24 

Conjunctiva 26,  50 

Conjunctival  fornix 27,  50 

Cilia 27 

Chalazion . . . , 36 

Contusions 37 

Canals,  hygrophthalmic 38 

Canal  of  Petit 96,  112,  113 

Conjunctivitis  catarrhalis 51 

' '  purulenta 54- 


INDEX.  147 

PAGE. 

Contagious  ophthalmia 54 

Canal  of  Cloquet 113 

Crede's  method 56 

Cloquet,   canal  of 113 

Conjunctivitis  diptheretica 56 

"  trachomatosa 57 

Crystalline  lens 113 

Conjunctivitis  phlyctenulosa 60 

Cataract 115 

Conjunctival  tumors 63 

Cancer 64 

Cornea.  J 65 

Corneal  injuries 67 

Canal  of  Schleram 121 

Corneal  wounds G7 

"       bums 68 

"      abrasions 68 

"       epithelium 68 

Conjunctivitis  verminosa 125 

Cornea,   imflamation  of 68 

"         staphyloma  of 69 

Cysticercus 125 

Corneal  abscess    72 

"       ulcer 72 

Catoptric  test 131 

Cataract,  anterior  capsular 73 

Conjugate  foci I33 

Cicatricial  staphyloma 78 

Corpora  nigra 95 

Ciliary  nerves,  short 85 

Circulus  iridis  major 86 

"  *'      minor Rft 


148  INDEX. 

PAOK. 

Ciliary  body 94 

Canal  of  Fontana OS 

Ciliary  canal 96 

Corpus  ciliare 96 

Canaera  obscura 5 

<:hief  Axis 10 

Center,  optical... 10 

Colors,  primary 12 

Cyclitis 98- 

Choroid 105 

Canthi 24 

Distance  focal 10 

Dilator  pupillae 14,  85 

Duration  of  luminous  impressions 16 

Degree      "        "  "  16" 

Duret— stricture  of  lachrymal 42,  43 

Dacryocystitis  catarrhalis 42 

"  phlegmonosa 44 

Diffuse  keratitis 71 

Differential  diagnosis  between— 

Conjunctivitis ) 

Scleritis Y 81 

Iritis ) 

Distichiasis 33r 

Diphtheritic  conjunctivitis 56 

Duct — nasal 39 

Dacryoadenitis 39 

De  Wecker 58,  81 

Dislocation  lachrymal  gland 40 

Differential  diagnosis  between- 
Con  junctivitis  catarrhalis T 

Iritis „,        ■ 

^      ,  y 61,    2r 

Trachoma ' 


Conjunctivitis  folliculosis j 


INDEX.  14^ 

PAGE. 

Dermoid  tumor 64 

Decemet's  membrane 66  . 

Equator 16^ 

Ether  waves Ig 

Eyelids 20,  24 

Exophthalraus 22,  123 

Enucleation 23,  99,  125- 

Eyelashes 2V 

Eetropium 31,  34 

Epilation 31 

Ectopia  lentis 116 

Entropium 33 

Excretory  apparatus 41 

Epiphora 41,  42 

Echinococcus 125 

External  rectus  muscle 47 

Exenteration 127 

Episcleritis 81 

Fontana's  spaces 121 

Fornix 50,  27 

Filaria  lachryraalia 125 

"      papillosa 125 

Fistula  lachrymaiia 45 

Fontana,  canal  of 96 

Focal  distance 10 

Field  of  projection 12 

Fovea  centralis 110 

Fossa,  temporal 20 

•'        patellaris 112 

Foramen,   optic 21 

Glands  of  Moll... 27 

Glands,  meibomian 28 


150  INDEX. 

PAGE. 

Gland  of  Harder 30 

Gland,  lachrymal 20,  38 

Great  oblique  muscle 48 

Gonorrhoeal  conjunctivitis 55 

"  ophthalmia 55 

Granular  lids 57 

"  conjunctivitis 57 

Glaucoma 121 

Humor,  vitreous 113 

Hyaloid  membrane 112 

Haw 20,28 

Hyaloid  artery 112 

Hiatus,  orbital 20 

Helmholtz 128 

Harder's  gland 30 

Hordeolum ^ 32 

Hygrophthalmic  canals 38 

Hypertrophy  of  lachrymal  gland 40 

Hypopyon 72 

Hernia  of  cornea 73 

Introduction 5 

Image,  inverted 5,  15,  17 

Interstitial  keratitis 71 

Incidence,  angle  of 8 

Iris 11,  84,  86 

"  sphincter  muscle  of 14 

Impressions,  luminous 16 

Image,  position  of 17 

Inverted  image 5,  15,  17 

Injuries  of  sclera 83 

"       "  cornea 87 

Inflammation  of  cornea. ...  68 


INDEX.  151 

PAGE. 

Inferior  rectus  muscle 46 

Internal     "         "       47 

Inferior  oblique  "         48 

Iritic  angle 12t 

Iridectomy 91,  124 

Irido-cyclitis 99,  125 

Iris,  tumors  of 90 

Iridavulsion 91 

Irido,  choroiditis 99 

Internal  ophthalmia 110 

Jequirity  bean 58 

' '  infusion 77 

Keratitis 68 

"       vasculosa 70 

"       phlyctenulosa 70 

'•       interstitialis 71 

"       diffusa 71 

' '       parenchymatosa 71 

"       suppurativa 71 

Keratocele 73 

Lamina  cribrosa 79 

Lids,  Abscess  of 30 

Ligamentum  pectinatum 84 

Lachrymal  gland 20,  38 

"  "      dislocation  of  40 

"  sac 39 

"  gland,  hypertrophy  of 40 

"  duct 42   43 

'*  fistula 45 

Luminous  impressions 16 

Lids,  granular 57 

Levator  palpebrae  superioris  muscle 24  2ft 


152  INDEX. 

PAGE. 

Light. 8,  11,  18- 

Lens 113 

Ligamentum  pectinatum  iridis 96,  121 

Liebold 127 

lienticula  fossa 112 

Leucoma 77 

"       adherans 77 

Muscle — Oiliary,  of  Riolini 24 

Posterior  rectus 46 

Retractor  oculi 46 

Superior  rectus 46' 

Inferior       "     46 

Internal      "     47 

External     " 47 

Superior  oblique 48 

Inferior       "      .48 

Temporal  muscle 20 

Obicularis 24 

Levator  palpebrae  superioris 24,  26 

Muscle  of  accommodation 97 

Meibomian  follicles 50 

Moll,  glands  of. 27 

Meibomian  glands 28 

Membrane  nictatans 20,  28 

Method,  Crede's 56 

Membrane,    Bowman's 65 

• '  Decemet's 66 

"  Hyaloid -. 112 

"  Ocular 20 

Meridians 16 

Mites 124 

Motor-oculi  nerves 14 


INDEX.  153^ 

PAGE. 

Macula  lutea 15,  73,  110 

Membrana  pupillaris  persistans 90 

Moon  blindness 99^ 

Nubecula 73 

Nebula 73,  77 

Nictatans,   Membrana 20 

Nerve,  optic 79,  117 

"        oculo-inotor 48 

Nerves,  short  ciliary 85 

"        fifth  pair 98 

Nictitation 33 

Nasal  duct 39 

Oblique  illumination • 132 

Optic  nerve 21,  79,  117 

"        '*       atrophy  of 119 

"      axis 16,  17 

**      foramen 21 

Optical  center IC 

Orbits 7 

Orbital  cavity.   19 

Ocukr  sheath 20 

"      membrane 20 

Orbital  hiatus 20 

Ophthalmic  artery 21 

Orbital  cellulitis 22 

"        periostitis 23 

' '       tumors 23 

Ophthalmoscope 128 

Orbicularis  muscle 24 

Ora  serrata 94,  107 

Ophthalmia,  sympathetic 99,    103 

"  tarsi 81 


154  INDEX. 

PAGE. 

Ophthalmia,  periodic 99 

Operation,  Wharton  Jones 35 

Opthalmia,    internal 110 

Oeulo-motor  nerve 48 

Onyx  72 

Operation,  Saemisches 74 

Ophthalmia  contagiosa C4 

"  catarrhalis 51 

*  *  gonorrhoeal 55 

"  neonatorum 55 

Phlyctenular  conjunctivitis 60 

"  keratitis 70 

Punctum  lachrymalia 24 

Parenchymatous  keratitis 71 

Phtheriasis 31 

Paracentesis 74,  75 

Ptosis 33 

Pannus 76 

Puncta 39 

Porous  opticus 79 

Phlegmonous  dacryocystitis 44 

Posterior  retractor  oculi  muscle 46 

Pink  eye 51 

Paralysis  of  muscles 48 

Purulent  conjunctivitis 54 

Poles  of  the  eye 16 

Petit,  Canal  of 112,  113,  96 

Panophthalmitis 22,  98 

Position  of  image 17 

Periorbita • 20 

Pterygium 63 

Pinguecula 63 


INDEX.  155 

PAGE. 

Periostitis— Orbital 23 

Palpebrae 20,  24 

Preface 4 

Persistent  hyaloid  artery 113 

Prism 12 

Primary  colors 12 

Projection,  field  of 12 

Purple,  visual 13 

Pentastoma  Tsenoides 125 

Periodic  ophthalmia 99 

Pectinate  ligament 96 

Reflection,  angle  of 8 

Rods  and  cones 15 

Riolini,  ciliary  muscle  of 24 

Recurrent  opthalmia     99 

Retina 106 

Roemer 18 

Sound  waves 18 

Squint 49 

Staphyloma  of  cornea 69 

Suppurative  keratitis 71 

Spherical  aberration 11 

Superior  rectus  muscle 46 

Staphyloma,  cicatricial 78 

Sphincter  muscle  of  the  iris 14 

Simpathetic  cervical 14 

Sylvius,  aqueduct  of 15 

Sclera 79 

Staphyloma  of  sclerotic 81 

Sight 18 

Steele 13 

Sheath,  ocular 0 


156  INDEX. 

FAOK. 

^lerotic,  staphyloma  of el 

Scleritis 18 

Sclera,  annular  staphyloma  of 83 

Sebacious  glands 27 

Staphyloma,  annular  of  sclera 83 

Stye 32 

"Symblepharon 35 

Sac,  lachrymal 39 

Soot-balls 85 

Sphincter  pupillae 85 

Short  ciliary  nerves 85 

Stricture,  lachrymal  duct 42,  43 

Synechia. ,   87 

Superior  oblique  muscle 48 

Small  "  "      48 

Strabismus 49 

Sympathathic  ophthalmia 103 

Snow  blindness 117 

Spaces  of  Fontana 121 

Synechia,  anterior 73 

Saemische's  operatio^ 74 

Schlemm,  canal  of 121 

Tinia  tarsi 31 

Tarsi        26 

Tumors  of  conjunctiva 63 

Tract,  uveal  84 

Third  pair  of  nerves 14 

Tumors  of  iris 90 

Tapetum 7 

Test,  catoptric 131 

Trigeminus 14 

Temporal  fossa 20 


INDEX.  157 

PAOC. 

Tumors,  dermoid 64 

Tenon's  capsule 21 

Tumors  of  orbit 23 

Trachoma 57 

Trichiasis 33 

Uveal  tract 84 

Uvea 85 

Ulcus  cornea 72 

Visual  purple 18 

Vision 7 

Visual  axis 16 

Vascular  keratitis 70 

Venae  vorticosae 105 

Vitreous  humor 112 

Von  Graefe 124 

Warts 64 

Wounds  of  cornea    67 

"  lids 37 

Xerophthalmia 63 

Yellow  spot...  15,  17,  110 

Zinn,  zonule  of 14,  94,  112,  113 


BIBLIOGRAPHY. 

Ophthalmic  and  Otic  Memoranda Roosa. 

Encyclop.  Brit.  Article  Optics. 

Physiology  of  Domestic  Animals Smith. 

Ocular  Therapeutics De.Wecker^ 

Diseases  of  the  Eye Notes. 

Physics Steele. 

Ophthalmic  Diseases  and  Therapeutics.  ..Norton. 
Comparative  Anatomy  of  the  Domestic 

animals Chauveau. 

Popular  Scientific  Lectures IIelmholtz.. 

Six  Lectures  on  Light Tyndall. 

Journal  of   Ophthalmology,  Otology  and 

Laryngology,  N.  Y. 

Yade  mecum  of  Equine  Anatomy Liautakd. 

Diseases  of  the  horse,  B.  A.  L,  1890 Law. 

Pathology  and  Treatment  of  Glaucoma . .  .Smith. 

Lectures  on  the  Human  Eye Alt. 

Diseases  of  the  Eye Berry. 

Diseases  of  the  Eye Nettleship. 

American  Journal  of  Ophthalmology St.  Louis. 


JAN  1  .a  2000 

.UN -2  0  im 


